Category: Data Breaches

The stalkerware company LetMeSpy has been hacked:

TechCrunch reviewed the leaked data, which included years of victims’ call logs and text messages dating back to 2013.

The database we reviewed contained current records on at least 13,000 compromised devices, though some of the devices shared little to no data with LetMeSpy. (LetMeSpy claims to delete data after two months of account inactivity.)

[…]

The database also contained over 13,400 location data points for several thousand victims. Most of the location data points are centered over population hotspots, suggesting the majority of victims are located in the United States, India and Western Africa.

The data also contained the spyware’s master database, including information about 26,000 customers who used the spyware for free and the email addresses of customers who bought paying subscriptions.

The leaked data contains no identifying information, which means people whose data was leaked can’t be notified. (This is actually much more complicated than it might seem, because alerting the victims often means alerting the stalker—which can put the victims into unsafe situations.)

Data breaches have become increasingly common in recent years, and they can have a significant impact on merger and acquisition (M&A) deals. In this article, we will explore the influence of data breaches on M&A deals and the steps that companies can take to minimize their risks.

Information breaches can have a severe impact on M&A deals because they can compromise the confidentiality, integrity, and availability of sensitive data. A data breach can expose sensitive information, such as financial statements, customer data, intellectual property, and other confidential information, to unauthorized parties. This can lead to reputational damage, legal liabilities, and financial losses for both the acquirer and the target company.

As a result, acquirers are increasingly scrutinizing the target company’s cybersecurity posture as part of their due diligence process. They want to ensure that the target company has robust security controls in place to protect their data and that any past breaches have been properly remediated. In some cases, data breaches can even derail M&A deals entirely.

In addition, data breaches can have a significant impact on the valuation of the target company. Acquirers may reduce their offer price or include more extensive representations and warranties in the acquisition agreement to protect themselves from potential liabilities.

To minimize the risks of data breaches in M&A deals, companies should take proactive steps to strengthen their cybersecurity posture. This includes implementing robust security controls, conducting regular vulnerability assessments and penetration testing, and developing an incident response plan to address data breaches promptly.

Companies should also conduct thorough due diligence on potential acquisition targets’ cybersecurity posture to identify any potential risks and evaluate the target’s overall security posture. This will help acquirers make informed decisions and mitigate any risks associated with the acquisition.

In conclusion, data breaches can have a significant impact on M&A deals. Companies should take proactive steps to strengthen their cybersecurity posture, conduct thorough due diligence, and evaluate potential risks to minimize the impact of data breaches on M&A deals. By doing so, companies can protect their sensitive data, reputation, and financial assets from potential harm.

The post Influence of data breaches on Merger and Acquisition deals appeared first on Cybersecurity Insiders.

Google says it has suspended the app for the Chinese e-commerce giant Pinduoduo after malware was found in versions of the software. The move comes just weeks after Chinese security researchers published an analysis suggesting the popular e-commerce app sought to seize total control over affected devices by exploiting multiple security vulnerabilities in a variety of Android-based smartphones.

In November 2022, researchers at Google’s Project Zero warned about active attacks on Samsung mobile phones which chained together three security vulnerabilities that Samsung patched in March 2021, and which would have allowed an app to add or read any files on the device.

Google said it believes the exploit chain for Samsung devices belonged to a “commercial surveillance vendor,” without elaborating further. The highly technical writeup also did not name the malicious app in question.

On Feb. 28, 2023, researchers at the Chinese security firm DarkNavy published a blog post purporting to show evidence that a major Chinese ecommerce company’s app was using this same three-exploit chain to read user data stored by other apps on the affected device, and to make its app nearly impossible to remove.

The three Samsung exploits that DarkNavy says were used by the malicious app. In November 2022, Google documented these three same vulnerabilities being used together to compromise Samsung devices.

DarkNavy likewise did not name the app they said was responsible for the attacks. In fact, the researchers took care to redact the name of the app from multiple code screenshots published in their writeup. DarkNavy did not respond to requests for clarification.

“At present, a large number of end users have complained on multiple social platforms,” reads a translated version of the DarkNavy blog post. “The app has problems such as inexplicable installation, privacy leakage, and inability to uninstall.”

On March 3, 2023, a denizen of the now-defunct cybercrime community BreachForums posted a thread which noted that a unique component of the malicious app code highlighted by DarkNavy also was found in the ecommerce application whose name was apparently redacted from the DarkNavy analysis: Pinduoduo.

A Mar. 3, 2023 post on BreachForums, comparing the redacted code from the DarkNavy analysis with the same function in the Pinduoduo app available for download at the time.

On March 4, 2023, e-commerce expert Liu Huafang posted on the Chinese social media network Weibo that Pinduoduo’s app was using security vulnerabilities to gain market share by stealing user data from its competitors. That Weibo post has since been deleted.

On March 7, the newly created Github account Davinci1010 published a technical analysis claiming that until recently Pinduoduo’s source code included a “backdoor,” a hacking term used to describe code that allows an adversary to remotely and secretly connect to a compromised system at will.

That analysis includes links to archived versions of Pinduoduo’s app released before March 5 (version 6.50 and lower), which is when Davinci1010 says a new version of the app removed the malicious code.

Pinduoduo has not yet responded to requests for comment. Pinduoduo parent company PDD Holdings told Reuters Google has not shared details about why it suspended the app.

The company told CNN that it strongly rejects “the speculation and accusation that Pinduoduo app is malicious just from a generic and non-conclusive response from Google,” and said there were “several apps that have been suspended from Google Play at the same time.”

Pinduoduo is among China’s most popular e-commerce platforms, boasting approximately 900 million monthly active users.

Most of the news coverage of Google’s move against Pinduoduo emphasizes that the malware was found in versions of the Pinduoduo app available outside of Google’s app store — Google Play.

“Off-Play versions of this app that have been found to contain malware have been enforced on via Google Play Protect,” a Google spokesperson said in a statement to Reuters, adding that the Play version of the app has been suspended for security concerns.

However, Google Play is not available to consumers in China. As a result, the app will still be available via other mobile app stores catering to the Chinese market — including those operated by Huawei, Oppo, Tencent and VIVO.

Google said its ban did not affect the PDD Holdings app Temu, which is an online shopping platform in the United States. According to The Washington Post, four of the Apple App Store’s 10 most-downloaded free apps are owned by Chinese companies, including Temu and the social media network TikTok.

The Pinduoduo suspension comes as lawmakers in Congress this week are gearing up to grill the CEO of TikTok over national security concerns. TikTok, which is owned by Beijing-based ByteDance, said last month that it now has roughly 150 million monthly active users in the United States.

A new cybersecurity strategy released earlier this month by the Biden administration singled out China as the greatest cyber threat to the U.S. and Western interests. The strategy says China now presents the “broadest, most active, and most persistent threat to both government and private sector networks,” and says China is “the only country with both the intent to reshape the international order and, increasingly, the economic, diplomatic, military, and technological power to do so.”

A new breach involving data from nine million AT&T customers is a fresh reminder that your mobile provider likely collects and shares a great deal of information about where you go and what you do with your mobile device — unless and until you affirmatively opt out of this data collection. Here’s a primer on why you might want to do that, and how.

Image: Shutterstock

Telecommunications giant AT&T disclosed this month that a breach at a marketing vendor exposed certain account information for nine million customers. AT&T said the data exposed did not include sensitive information, such as credit card or Social Security numbers, or account passwords, but was limited to “Customer Proprietary Network Information” (CPNI), such as the number of lines on an account.

Certain questions may be coming to mind right now, like “What the heck is CPNI?” And, ‘If it’s so ‘customer proprietary,’ why is AT&T sharing it with marketers?” Also maybe, “What can I do about it?” Read on for answers to all three questions.

AT&T’s disclosure said the information exposed included customer first name, wireless account number, wireless phone number and email address. In addition, a small percentage of customer records also exposed the rate plan name, past due amounts, monthly payment amounts and minutes used.

CPNI refers to customer-specific “metadata” about the account and account usage, and may include:

-Called phone numbers
-Time of calls
-Length of calls
-Cost and billing of calls
-Service features
-Premium services, such as directory call assistance

According to a succinct CPNI explainer at TechTarget, CPNI is private and protected information that cannot be used for advertising or marketing directly.

“An individual’s CPNI can be shared with other telecommunications providers for network operating reasons,” wrote TechTarget’s Gavin Wright. “So, when the individual first signs up for phone service, this information is automatically shared by the phone provider to partner companies.”

Is your mobile Internet usage covered by CPNI laws? That’s less clear, as the CPNI rules were established before mobile phones and wireless Internet access were common. TechTarget’s CPNI primer explains:

“Under current U.S. law, cellphone use is only protected as CPNI when it is being used as a telephone. During this time, the company is acting as a telecommunications provider requiring CPNI rules. Internet use, websites visited, search history or apps used are not protected CPNI because the company is acting as an information services provider not subject to these laws.”

Hence, the carriers can share and sell this data because they’re not explicitly prohibited from doing so. All three major carriers say they take steps to anonymize the customer data they share, but researchers have shown it is not terribly difficult to de-anonymize supposedly anonymous web-browsing data.

“Your phone, and consequently your mobile provider, know a lot about you,” wrote Jack Morse for Mashable. “The places you go, apps you use, and the websites you visit potentially reveal all kinds of private information — e.g. religious beliefs, health conditions, travel plans, income level, and specific tastes in pornography. This should bother you.”

Happily, all of the U.S. carriers are required to offer customers ways to opt out of having data about how they use their devices shared with marketers. Here’s a look at some of the carrier-specific practices and opt-out options.

AT&T

AT&T’s policy says it shares device or “ad ID”, combined with demographics including age range, gender, and ZIP code information with third parties which explicitly include advertisers, programmers, and networks, social media networks, analytics firms, ad networks and other similar companies that are involved in creating and delivering advertisements.

AT&T said the data exposed on 9 million customers was several years old, and mostly related to device upgrade eligibility. This may sound like the data went to just one of its partners who experienced a breach, but in all likelihood it also went to hundreds of AT&T’s partners.

AT&T’s CPNI opt-out page says it shares CPNI data with several of its affiliates, including WarnerMedia, DirecTV and Cricket Wireless. Until recently, AT&T also shared CPNI data with Xandr, whose privacy policy in turn explains that it shares data with hundreds of other advertising firms. Microsoft bought Xandr from AT&T last year.

T-MOBILE

According to the Electronic Privacy Information Center (EPIC), T-Mobile seems to be the only company out of the big three to extend to all customers the rights conferred by the California Consumer Privacy Act (CCPA).

EPIC says T-Mobile customer data sold to third parties uses another unique identifier called mobile advertising IDs or “MAIDs.” T-Mobile claims that MAIDs don’t directly identify consumers, but under the CCPA MAIDs are considered “personal information” that can be connected to IP addresses, mobile apps installed or used with the device, any video or content viewing information, and device activity and attributes.

T-Mobile customers can opt out by logging into their account and navigating to the profile page, then to “Privacy and Notifications.” From there, toggle off the options for “Use my data for analytics and reporting” and “Use my data to make ads more relevant to me.”

VERIZON

Verizon’s privacy policy says it does not sell information that personally identities customers (e.g., name, telephone number or email address), but it does allow third-party advertising companies to collect information about activity on Verizon websites and in Verizon apps, through MAIDs, pixels, web beacons and social network plugins.

According to Wired.com’s tutorial, Verizon users can opt out by logging into their Verizon account through a web browser or the My Verizon mobile app. From there, select the Account tab, then click Account Settings and Privacy Settings on the web. For the mobile app, click the gear icon in the upper right corner and then Manage Privacy Settings.

On the privacy preferences page, web users can choose “Don’t use” under the Custom Experience section. On the My Verizon app, toggle any green sliders to the left.

EPIC notes that all three major carriers say resetting the consumer’s device ID and/or clearing cookies in the browser will similarly reset any opt-out preferences (i.e., the customer will need to opt out again), and that blocking cookies by default may also block the opt-out cookie from being set.

T-Mobile says its opt out is device-specific and/or browser-specific. “In most cases, your opt-out choice will apply only to the specific device or browser on which it was made. You may need to separately opt out from your other devices and browsers.”

Both AT&T and Verizon offer opt-in programs that gather and share far more information, including device location, the phone numbers you call, and which sites you visit using your mobile and/or home Internet connection. AT&T calls this their Enhanced Relevant Advertising Program; Verizon’s is called Custom Experience Plus.

In 2021, multiple media outlets reported that some Verizon customers were being automatically enrolled in Custom Experience Plus — even after those customers had already opted out of the same program under its previous name — “Verizon Selects.”

If none of the above opt out options work for you, at a minimum you should be able to opt out of CPNI sharing by calling your carrier, or by visiting one of their stores.

THE CASE FOR OPTING OUT

Why should you opt out of sharing CPNI data? For starters, some of the nation’s largest wireless carriers don’t have a great track record in terms of protecting the sensitive information that you give them solely for the purposes of becoming a customer — let alone the information they collect about your use of their services after that point.

In January 2023, T-Mobile disclosed that someone stole data on 37 million customer accounts, including customer name, billing address, email, phone number, date of birth, T-Mobile account number and plan details. In August 2021, T-Mobile acknowledged that hackers made off with the names, dates of birth, Social Security numbers and driver’s license/ID information on more than 40 million current, former or prospective customers who applied for credit with the company.

Last summer, a cybercriminal began selling the names, email addresses, phone numbers, SSNs and dates of birth on 23 million Americans. An exhaustive analysis of the data strongly suggested it all belonged to customers of one AT&T company or another. AT&T stopped short of saying the data wasn’t theirs, but said the records did not appear to have come from its systems and may be tied to a previous data incident at another company.

However frequently the carriers may alert consumers about CPNI breaches, it’s probably nowhere near often enough. Currently, the carriers are required to report a consumer CPNI breach only in cases “when a person, without authorization or exceeding authorization, has intentionally gained access to, used or disclosed CPNI.”

But that definition of breach was crafted eons ago, back when the primary way CPNI was exposed was through “pretexting,” such when the phone company’s employees are tricked into giving away protected customer data.

In January, regulators at the U.S. Federal Communications Commission (FCC) proposed amending the definition of “breach” to include things like inadvertent disclosure — such as when companies expose CPNI data on a poorly-secured server in the cloud. The FCC is accepting public comments on the matter until March 24, 2023.

While it’s true that the leak of CPNI data does not involve sensitive information like Social Security or credit card numbers, one thing AT&T’s breach notice doesn’t mention is that CPNI data — such as balances and payments made — can be abused by fraudsters to make scam emails and text messages more believable when they’re trying to impersonate AT&T and phish AT&T customers.

The other problem with letting companies share or sell your CPNI data is that the wireless carriers can change their privacy policies at any time, and you are assumed to be okay with those changes as long as you keep using their services.

For example, location data from your wireless device is most definitely CPNI, and yet until very recently all of the major carriers sold their customers’ real-time location data to third party data brokers without customer consent.

What was their punishment? In 2020, the FCC proposed fines totaling $208 million against all of the major carriers for selling their customers’ real-time location data. If that sounds like a lot of money, consider that all of the major wireless providers reported tens of billions of dollars in revenue last year (e.g., Verizon’s consumer revenue alone was more than $100 billion last year).

If the United States had federal privacy laws that were at all consumer-friendly and relevant to today’s digital economy, this kind of data collection and sharing would always be opt-in by default. In such a world, the enormously profitable wireless industry would likely be forced to offer clear financial incentives to customers who choose to share this information.

But until that day arrives, understand that the carriers can change their data collection and sharing policies when it suits them. And regardless of whether you actually read any notices about changes to their privacy policies, you will have agreed to those changes as long as you continue using their service.

Two U.S. men have been charged with hacking into a U.S. Drug Enforcement Agency (DEA) online portal that taps into 16 different federal law enforcement databases. Both are alleged to be part of a larger criminal organization that specializes in using fake emergency data requests from compromised police and government email accounts to publicly threaten and extort their victims.

Prosecutors for the Eastern District of New York today unsealed criminal complaints against Sagar Steven Singh — also known as “Weep” — a 19-year-old from Pawtucket, Rhode Island; and Nicholas Ceraolo, 25, of Queens, NY, who allegedly also went by the handles “Convict” and “Ominus.”

The Justice Department says Singh and Ceraolo belong to a group of cybercriminals known to its members as “ViLE,” who specialize in obtaining personal information about third-party victims, which they then use to harass, threaten or extort the victims, a practice known as “doxing.”

“ViLE is collaborative, and the members routinely share tactics and illicitly obtained information with each other,” prosecutors charged.

The government alleges the defendants and other members of ViLE use various methods to obtain victims’ personal information, including:

-tricking customer service employees;
-submitting fraudulent legal process to social media companies to elicit users’ registration information;
-co-opting and corrupting corporate insiders;
-searching public and private online databases;
-accessing a nonpublic United States government database without authorization
-unlawfully using official email accounts belonging to other countries.

The complaint says once they obtained a victim’s information, Singh and Ceraolo would post the information in an online forum. The government refers to this community only as “Forum-1,” saying that it is administered by the leader of ViLE (referenced in the complaint at CC-1).

“Victims are extorted into paying CC-1 to have their information removed from Forum-1,” prosecutors allege. “Singh also uses the threat of revealing personal information to extort victims into giving him access to their social media accounts, which Singh then resells.”

Sources tell KrebsOnSecurity in addition to being members of ViLE, both Weep and Ominous are or were staff members for Doxbin, a highly toxic online community that provides a forum for digging up personal information on people and posting it publicly. This is supported by the Doxin administrator’s claimed responsibility for a high-profile intrusion at the DEA’s law enforcement data sharing portal last year.

A screenshot of alleged access to the Drug Enforcement Agency’s intelligence sharing portal, shared by “KT,” the current administrator of the doxing and harassment community Doxbin.

The government alleges that on May 7, 2022, Singh used stolen credentials to log into a U.S. federal government portal without authorization. The complaint doesn’t specify which agency portal was hacked, but it does state that the portal included access to law enforcement databases that track narcotics seizures in the United States.

On May 12, 2022, KrebsOnSecurity broke the news that hackers had gained access to a DEA portal that taps into 16 different federal law enforcement databases. As reported at the time, the inside scoop on how that hack went down came from KT, the current administrator of the Doxbin and the individual referenced in the government’s complaint as “CC-1.”

Indeed, a screenshot of the ViLE group website includes the group’s official roster, which lists KT at the top, followed by Weep and Ominus.

A screenshot of the website for the cybercriminal group “ViLE.” Image: USDOJ.

In March 2022, KrebsOnSecurity warned that multiple cybercrime groups were finding success with fraudulent Emergency Data Requests (EDRs), wherein the hackers use compromised police and government email accounts to file warrantless data requests with social media firms and mobile telephony providers, attesting that the information being requested can’t wait for a warrant because it relates to an urgent matter of life and death.

That story showed that the previous owner of the Doxbin also was part of a teenage hacking group that specialized in offering fake EDRs as a service on the dark web.

Prosecutors say they tied Singh to the government portal hack because he connected to it from an Internet address that he’d previously used to access a social media account registered in his name. When they raided Singh’s residence on Sept. 8, 2022 and seized his devices, investigators with Homeland Security found a cellular phone and laptop that allegedly “contained extensive evidence of access to the Portal.”

The complaint alleges that between February 2022 and May 2022, Ceraolo used an official email account belonging to a Bangladeshi police official to pose as a police officer in communication with U.S.-based social media platforms.

“In these communications, Ceraolo requested personal information about users of these platforms, under the false pretense that the users were committing crimes or in life-threatening danger,” the complaint states.

For example, on or about March 13, 2022, Ceraolo allegedly used the Bangladeshi police email account to falsely claim that the target of the EDR had sent bomb threats, distributed child pornography and threatened officials of the Bangladeshi government.

On or about May 9, 2022, the government says, Singh sent a friend screenshots of text messages between himself and someone he had doxed on the Doxbin and was trying to extort for their Instagram handle. The data included the victim’s Social Security number, driver’s license number, cellphone number, and home address.

“Look familiar?” Singh allegedly wrote to the victim. “You’re gonna comply to me if you don’t want anything negative to happen to your parents. . . I have every detail involving your parents . . . allowing me to do whatever I desire to them in malicious ways.”

Neither of the defendants could be immediately reached for comment. KT, the current administrator of the Doxbin, has not responded to requests for comment.

Ceraolo is a self-described security researcher who has been credited in many news stories over the years with discovering security vulnerabilities at AT&T, T-Mobile, Comcast and Cox Communications.

Ceraolo’s stated partner in most of these discoveries — a 30-year-old Connecticut man named Ryan “Phobia” Stevenson — was charged in 2019 with being part of a group that stole millions of dollars worth of cryptocurrencies via SIM-swapping, a crime that involves tricking a mobile provider into routing a target’s calls and text messages to another device.

In 2018, KrebsOnSecurity detailed how Stevenson earned bug bounty rewards and public recognition from top telecom companies for finding and reporting security holes in their websites, all the while secretly peddling those same vulnerabilities to cybercriminals.

According to the Justice Department, if convicted Ceraolo faces up to 20 years’ imprisonment for conspiracy to commit wire fraud; both Ceraolo and Singh face five years’ imprisonment for conspiracy to commit computer intrusions.

A copy of the complaint against Ceraolo and Singh is here (PDF).

Image: Shutterstock.com

Three different cybercriminal groups claimed access to internal networks at communications giant T-Mobile in more than 100 separate incidents throughout 2022, new data suggests. In each case, the goal of the attackers was the same: Phish T-Mobile employees for access to internal company tools, and then convert that access into a cybercrime service that could be hired to divert any T-Mobile user’s text messages and phone calls to another device.

The conclusions above are based on an extensive analysis of Telegram chat logs from three distinct cybercrime groups or actors that have been identified by security researchers as particularly active in and effective at “SIM-swapping,” which involves temporarily seizing control over a target’s mobile phone number.

Countless websites and online services use SMS text messages for both password resets and multi-factor authentication. This means that stealing someone’s phone number often can let cybercriminals hijack the target’s entire digital life in short order — including access to any financial, email and social media accounts tied to that phone number.

All three SIM-swapping entities that were tracked for this story remain active in 2023, and they all conduct business in open channels on the instant messaging platform Telegram. KrebsOnSecurity is not naming those channels or groups here because they will simply migrate to more private servers if exposed publicly, and for now those servers remain a useful source of intelligence about their activities.

Each advertises their claimed access to T-Mobile systems in a similar way. At a minimum, every SIM-swapping opportunity is announced with a brief “Tmobile up!” or “Tmo up!” message to channel participants. Other information in the announcements includes the price for a single SIM-swap request, and the handle of the person who takes the payment and information about the targeted subscriber.

The information required from the customer of the SIM-swapping service includes the target’s phone number, and the serial number tied to the new SIM card that will be used to receive text messages and phone calls from the hijacked phone number.

Initially, the goal of this project was to count how many times each entity claimed access to T-Mobile throughout 2022, by cataloging the various “Tmo up!” posts from each day and working backwards from Dec. 31, 2022.

But by the time we got to claims made in the middle of May 2022, completing the rest of the year’s timeline seemed unnecessary. The tally shows that in the last seven-and-a-half months of 2022, these groups collectively made SIM-swapping claims against T-Mobile on 104 separate days — often with multiple groups claiming access on the same days.

The 104 days in the latter half of 2022 in which different known SIM-swapping groups claimed access to T-Mobile employee tools.

KrebsOnSecurity shared a large amount of data gathered for this story with T-Mobile. The company declined to confirm or deny any of these claimed intrusions. But in a written statement, T-Mobile said this type of activity affects the entire wireless industry.

“And we are constantly working to fight against it,” the statement reads. “We have continued to drive enhancements that further protect against unauthorized access, including enhancing multi-factor authentication controls, hardening environments, limiting access to data, apps or services, and more. We are also focused on gathering threat intelligence data, like what you have shared, to help further strengthen these ongoing efforts.”

TMO UP!

While it is true that each of these cybercriminal actors periodically offer SIM-swapping services for other mobile phone providers — including AT&T, Verizon and smaller carriers — those solicitations appear far less frequently in these group chats than T-Mobile swap offers. And when those offers do materialize, they are considerably more expensive.

The prices advertised for a SIM-swap against T-Mobile customers in the latter half of 2022 ranged between USD $1,000 and $1,500, while SIM-swaps offered against AT&T and Verizon customers often cost well more than twice that amount.

To be clear, KrebsOnSecurity is not aware of specific SIM-swapping incidents tied to any of these breach claims. However, the vast majority of advertisements for SIM-swapping claims against T-Mobile tracked in this story had two things in common that set them apart from random SIM-swapping ads on Telegram.

First, they included an offer to use a mutually trusted “middleman” or escrow provider for the transaction (to protect either party from getting scammed). More importantly, the cybercriminal handles that were posting ads for SIM-swapping opportunities from these groups generally did so on a daily or near-daily basis — often teasing their upcoming swap events in the hours before posting a “Tmo up!” message announcement.

In other words, if the crooks offering these SIM-swapping services were ripping off their customers or claiming to have access that they didn’t, this would be almost immediately obvious from the responses of the more seasoned and serious cybercriminals in the same chat channel.

There are plenty of people on Telegram claiming to have SIM-swap access at major telecommunications firms, but a great many such offers are simply four-figure scams, and any pretenders on this front are soon identified and banned (if not worse).

One of the groups that reliably posted “Tmo up!” messages to announce SIM-swap availability against T-Mobile customers also reliably posted “Tmo down!” follow-up messages announcing exactly when their claimed access to T-Mobile employee tools was discovered and revoked by the mobile giant.

A review of the timestamps associated with this group’s incessant “Tmo up” and “Tmo down” posts indicates that while their claimed access to employee tools usually lasted less than an hour, in some cases that access apparently went undiscovered for several hours or even days.

TMO TOOLS

How could these SIM-swapping groups be gaining access to T-Mobile’s network as frequently as they claim? Peppered throughout the daily chit-chat on their Telegram channels are solicitations for people urgently needed to serve as “callers,” or those who can be hired to social engineer employees over the phone into navigating to a phishing website and entering their employee credentials.

Allison Nixon is chief research officer for the New York City-based cybersecurity firm Unit 221B. Nixon said these SIM-swapping groups will typically call employees on their mobile devices, pretend to be someone from the company’s IT department, and then try to get the person on the other end of the line to visit a phishing website that mimics the company’s employee login page.

Nixon argues that many people in the security community tend to discount the threat from voice phishing attacks as somehow “low tech” and “low probability” threats.

“I see it as not low-tech at all, because there are a lot of moving parts to phishing these days,” Nixon said. “You have the caller who has the employee on the line, and the person operating the phish kit who needs to spin it up and down fast enough so that it doesn’t get flagged by security companies. Then they have to get the employee on that phishing site and steal their credentials.”

In addition, she said, often there will be yet another co-conspirator whose job it is to use the stolen credentials and log into employee tools. That person may also need to figure out how to make their device pass “posture checks,” a form of device authentication that some companies use to verify that each login is coming only from employee-issued phones or laptops.

For aspiring criminals with little experience in scam calling, there are plenty of sample call transcripts available on these Telegram chat channels that walk one through how to impersonate an IT technician at the targeted company — and how to respond to pushback or skepticism from the employee. Here’s a snippet from one such tutorial that appeared recently in one of the SIM-swapping channels:

“Hello this is James calling from Metro IT department, how’s your day today?”

(yea im doing good, how r u)

i’m doing great, thank you for asking

i’m calling in regards to a ticket we got last week from you guys, saying you guys were having issues with the network connectivity which also interfered with [Microsoft] Edge, not letting you sign in or disconnecting you randomly. We haven’t received any updates to this ticket ever since it was created so that’s why I’m calling in just to see if there’s still an issue or not….”

TMO DOWN!

The TMO UP data referenced above, combined with comments from the SIM-swappers themselves, indicate that while many of their claimed accesses to T-Mobile tools in the middle of 2022 lasted hours on end, both the frequency and duration of these events began to steadily decrease as the year wore on.

T-Mobile declined to discuss what it may have done to combat these apparent intrusions last year. However, one of the groups began to complain loudly in late October 2022 that T-Mobile must have been doing something that was causing their phished access to employee tools to die very soon after they obtained it.

One group even remarked that they suspected T-Mobile’s security team had begun monitoring their chats.

Indeed, the timestamps associated with one group’s TMO UP/TMO DOWN notices show that their claimed access was often limited to less than 15 minutes throughout November and December of 2022.

Whatever the reason, the calendar graphic above clearly shows that the frequency of claimed access to T-Mobile decreased significantly across all three SIM-swapping groups in the waning weeks of 2022.

SECURITY KEYS

T-Mobile US reported revenues of nearly $80 billion last year. It currently employs more than 71,000 people in the United States, any one of whom can be a target for these phishers.

T-Mobile declined to answer questions about what it may be doing to beef up employee authentication. But Nicholas Weaver, a researcher and lecturer at University of California, Berkeley’s International Computer Science Institute, said T-Mobile and all the major wireless providers should be requiring employees to use physical security keys for that second factor when logging into company resources.

A U2F device made by Yubikey.

“These breaches should not happen,” Weaver said. “Because T-Mobile should have long ago issued all employees security keys and switched to security keys for the second factor. And because security keys provably block this style of attack.”

The most commonly used security keys are inexpensive USB-based devices. A security key implements a form of multi-factor authentication known as Universal 2nd Factor (U2F), which allows the user to complete the login process simply by inserting the USB key and pressing a button on the device. The key works without the need for any special software drivers.

The allure of U2F devices for multi-factor authentication is that even if an employee who has enrolled a security key for authentication tries to log in at an impostor site, the company’s systems simply refuse to request the security key if the user isn’t on their employer’s legitimate website, and the login attempt fails. Thus, the second factor cannot be phished, either over the phone or Internet.

THE ROLE OF MINORS IN SIM-SWAPPING

Nixon said one confounding aspect of SIM-swapping is that these criminal groups tend to recruit teenagers to do their dirty work.

“A huge reason this problem has been allowed to spiral out of control is because children play such a prominent role in this form of breach,” Nixon said.

Nixon said SIM-swapping groups often advertise low-level jobs on places like Roblox and Minecraft, online games that are extremely popular with young adolescent males.

“Statistically speaking, that kind of recruiting is going to produce a lot of people who are underage,” she said. “They recruit children because they’re naive, you can get more out of them, and they have legal protections that other people over 18 don’t have.”

For example, she said, even when underage SIM-swappers are arrested, the offenders tend to go right back to committing the same crimes as soon as they’re released.

In January 2023, T-Mobile disclosed that a “bad actor” stole records on roughly 37 million current customers, including their name, billing address, email, phone number, date of birth, and T-Mobile account number.

In August 2021, T-Mobile acknowledged that hackers made off with the names, dates of birth, Social Security numbers and driver’s license/ID information on more than 40 million current, former or prospective customers who applied for credit with the company. That breach came to light after a hacker began selling the records on a cybercrime forum.

In the shadow of such mega-breaches, any damage from the continuous attacks by these SIM-swapping groups can seem insignificant by comparison. But Nixon says it’s a mistake to dismiss SIM-swapping as a low volume problem.

“Logistically, you may only be able to get a few dozen or a hundred SIM-swaps in a day, but you can pick any customer you want across their entire customer base,” she said. “Just because a targeted account takeover is low volume doesn’t mean it’s low risk. These guys have crews that go and identify people who are high net worth individuals and who have a lot to lose.”

Nixon said another aspect of SIM-swapping that causes cybersecurity defenders to dismiss the threat from these groups is the perception that they are full of low-skilled “script kiddies,” a derisive term used to describe novice hackers who rely mainly on point-and-click hacking tools.

“They underestimate these actors and say this person isn’t technically sophisticated,” she said. “But if you’re rolling around in millions worth of stolen crypto currency, you can buy that sophistication. I know for a fact some of these compromises were at the hands of these ‘script kiddies,’ but they’re not ripping off other people’s scripts so much as hiring people to make scripts for them. And they don’t care what gets the job done, as long as they get to steal the money.”

In early 2021, IEEE Security and Privacy asked a number of board members for brief perspectives on the SolarWinds incident while it was still breaking news. This was my response.

The penetration of government and corporate networks worldwide is the result of inadequate cyberdefenses across the board. The lessons are many, but I want to focus on one important one we’ve learned: the software that’s managing our critical networks isn’t secure, and that’s because the market doesn’t reward that security.

SolarWinds is a perfect example. The company was the initial infection vector for much of the operation. Its trusted position inside so many critical networks made it a perfect target for a supply-chain attack, and its shoddy security practices made it an easy target.

Why did SolarWinds have such bad security? The answer is because it was more profitable. The company is owned by Thoma Bravo partners, a private-equity firm known for radical cost-cutting in the name of short-term profit. Under CEO Kevin Thompson, the company underspent on security even as it outsourced software development. The New York Times reports that the company’s cybersecurity advisor quit after his “basic recommendations were ignored.” In a very real sense, SolarWinds profited because it secretly shifted a whole bunch of risk to its customers: the US government, IT companies, and others.

This problem isn’t new, and, while it’s exacerbated by the private-equity funding model, it’s not unique to it. In general, the market doesn’t reward safety and security—especially when the effects of ignoring those things are long term and diffuse. The market rewards short-term profits at the expense of safety and security. (Watch and see whether SolarWinds suffers any long-term effects from this hack, or whether Thoma Bravo’s bet that it could profit by selling an insecure product was a good one.)

The solution here is twofold. The first is to improve government software procurement. Software is now critical to national security. Any system of procuring that software needs to evaluate the security of the software and the security practices of the company, in detail, to ensure that they are sufficient to meet the security needs of the network they’re being installed in. If these evaluations are made public, along with the list of companies that meet them, all network buyers can benefit from them. It’s a win for everybody.

But that isn’t enough; we need a second part. The only way to force companies to provide safety and security features for customers is through regulation. This is true whether we want seat belts in our cars, basic food safety at our restaurants, pajamas that don’t catch on fire, or home routers that aren’t vulnerable to cyberattack. The government needs to set minimum security standards for software that’s used in critical network applications, just as it sets software standards for avionics.

Without these two measures, it’s just too easy for companies to act like SolarWinds: save money by skimping on safety and security and hope for the best in the long term. That’s the rational thing for companies to do in an unregulated market, and the only way to change that is to change the economic incentives.

This essay originally appeared in the March/April 2021 issue of IEEE Security & Privacy.” I forgot to publish it here.

On Dec. 23, 2022, KrebsOnSecurity alerted big-three consumer credit reporting bureau Experian that identity thieves had worked out how to bypass its security and access any consumer’s full credit report — armed with nothing more than a person’s name, address, date of birth, and Social Security number. Experian fixed the glitch, but remained silent about the incident for a month. This week, however, Experian acknowledged that the security failure persisted for nearly seven weeks, between Nov. 9, 2022 and Dec. 26, 2022.

The tip about the Experian weakness came from Jenya Kushnir, a security researcher living in Ukraine who said he discovered the method being used by identity thieves after spending time on Telegram chat channels dedicated to cybercrime.

Normally, Experian’s website will ask a series of multiple-choice questions about one’s financial history, as a way of validating the identity of the person requesting the credit report. But Kushnir said the crooks learned they could bypass those questions and trick Experian into giving them access to anyone’s credit report, just by editing the address displayed in the browser URL bar at a specific point in Experian’s identity verification process.

When I tested Kushnir’s instructions on my own identity at Experian, I found I was able to see my report even though Experian’s website told me it didn’t have enough information to validate my identity. A security researcher friend who tested it at Experian found she also could bypass Experian’s four or five multiple-choice security questions and go straight to her full credit report at Experian.

Experian acknowledged receipt of my Dec. 23 report four days later on Dec. 27, a day after Kushnir’s method stopped working on Experian’s website (the exploit worked as long as you came to Experian’s website via annualcreditreport.com — the site mandated to provide a free copy of your credit report from each of the major bureaus once a year).

Experian never did respond to official requests for comment on that story. But earlier this week, I received an otherwise unhelpful letter via snail mail from Experian (see image above), which stated that the weakness we reported persisted between Nov. 9, 2022 and Dec. 26, 2022.

“During this time period, we experienced an isolated technical issue where a security feature may not have functioned,” Experian explained.

It’s not entirely clear whether Experian sent me this paper notice because they legally had to, or if they felt I deserved a response in writing and thought maybe they’d kill two birds with one stone. But it’s pretty crazy that it took them a full month to notify me about the potential impact of a security failure that I notified them about.

It’s also a little nuts that Experian didn’t simply include a copy of my current credit report along with this letter, which is confusingly worded and reads like they suspect someone other than me may have been granted access to my credit report without any kind of screening or authorization.

After all, if I hadn’t authorized the request for my credit file that apparently prompted this letter (I had), that would mean the thieves already had my report. Shouldn’t I be granted the same visibility into my own credit file as them?

Instead, their woefully inadequate letter once again puts the onus on me to wait endlessly on hold for an Experian representative over the phone, or sign up for a free year’s worth of Experian monitoring my credit report.

As it stands, using Kushnir’s exploit was the only time I’ve ever been able to get Experian’s website to cough up a copy of my credit report. To make matters worse, a majority of the information in that credit report is not mine. So I’ve got that to look forward to.

If there is a silver lining here, I suppose that if I were Experian, I probably wouldn’t want to show Brian Krebs his credit file either. Because it’s clear this company has no idea who I really am. And in a weird, kind of sad way I guess, that makes me happy.

For thoughts on what you can do to minimize your victimization by and overall worth to the credit bureaus, see this section of the most recent Experian story.

T-Mobile today disclosed a data breach affecting tens of millions of customer accounts, its second major data exposure in as many years. In a filing with federal regulators, T-Mobile said an investigation determined that someone abused its systems to harvest subscriber data tied to approximately 37 million current customer accounts.

Image: customink.com

In a filing today with the U.S. Securities and Exchange Commission, T-Mobile said a “bad actor” abused an application programming interface (API) to hoover up data on roughly 37 million current postpaid and prepaid customer accounts. The data stolen included customer name, billing address, email, phone number, date of birth, T-Mobile account number, as well as information on the number of customer lines and plan features.

APIs are essentially instructions that allow applications to access data and interact with web databases. But left improperly secured, these APIs can be leveraged by malicious actors to mass-harvest information stored in those databases. In October, mobile provider Optus disclosed that hackers abused a poorly secured API to steal data on 10 million customers in Australia.

The company said it first learned of the incident on Jan. 5, 2022, and that an investigation determined the bad actor started abusing the API beginning around Nov. 25, 2022.

T-Mobile says it is in the process of notifying affected customers, and that no customer payment card data, passwords, Social Security numbers, driver’s license or other government ID numbers were exposed.

In August 2021, T-Mobile acknowledged that hackers made off with the names, dates of birth, Social Security numbers and driver’s license/ID information on more than 40 million current, former or prospective customers who applied for credit with the company. That breach came to light after a hacker began selling the records on a cybercrime forum.

Last year, T-Mobile agreed to pay $500 million to settle all class action lawsuits stemming from the 2021 breach. The company pledged to spend $150 million of that money toward beefing up its own cybersecurity.

In its filing with the SEC, T-Mobile suggested it was going to take years to fully realize the benefits of those cybersecurity improvements, even as it claimed that protecting customer data remains a top priority.

“As we have previously disclosed, in 2021, we commenced a substantial multi-year investment working with leading external cybersecurity experts to enhance our cybersecurity capabilities and transform our approach to cybersecurity,” the filing reads. “We have made substantial progress to date, and protecting our customers’ data remains a top priority.”

Despite this being the second major customer data spill in as many years, T-Mobile told the SEC the company does not expect this latest breach to have a material impact on its operations.

While that may seem like a daring thing to say in a data breach disclosure affecting a significant portion of your active customer base, consider that T-Mobile reported revenues of nearly $20 billion in the third quarter of 2022 alone. In that context, a few hundred million dollars every couple of years to make the class action lawyers go away is a drop in the bucket.

The settlement related to the 2021 breach says T-Mobile will make $350 million available to customers who file a claim. But here’s the catch: If you were affected by that 2021 breach and you haven’t filed a claim yet, please know that you have only three more days to do that.

If you were a T-Mobile customer affected by the 2021 incident, it is likely that T-Mobile has already made several efforts to notify you of your eligibility to file a claim, which includes a payout of at least $25, with the possibility of more for those who can document direct costs associated with the breach. OpenClassActions.com says the filing deadline is Jan. 23, 2023.

“If you opt for a cash payment you will receive an estimated $25.00,” the site explains. “If you reside in California, you will receive an estimated $100.00. Out of pocket losses can be reimbursed for up to $25,000.00. The amount that you claim from T-Mobile will be determined by the class action administrator based on how many people file a legitimate and timely claim form.”

There are currently no signs that hackers are selling this latest data haul from T-Mobile, but if the past is any teacher much of it will wind up posted online soon. It is a safe bet that scammers will use some of this information to target T-Mobile users with phishing messages, account takeovers and harassment.

T-Mobile customers should fully expect to see phishers taking advantage of public concern over the breach to impersonate the company — and possibly even send messages that include the recipient’s compromised account details to make the communications look more legitimate.

Data stolen and exposed in this breach may also be used for identity theft. Credit monitoring and ID theft protection services can help you recover from having your identity stolen, but most will do nothing to stop the ID theft from happening. If you want the maximum control over who should be able to view your credit or grant new lines of credit in your name, then a security freeze is your best option.

Regardless of which mobile provider you patronize, please consider removing your phone number from as many online accounts as you can. Many online services require you to provide a phone number upon registering an account, but in many cases that number can be removed from your profile afterwards.

Why do I suggest this? Many online services allow users to reset their passwords just by clicking a link sent via SMS, and this unfortunately widespread practice has turned mobile phone numbers into de facto identity documents. Which means losing control over your phone number thanks to an unauthorized SIM swap or mobile number port-out, divorce, job termination or financial crisis can be devastating.

Identity thieves have been exploiting a glaring security weakness in the website of Experian, one of the big three consumer credit reporting bureaus. Normally, Experian requires that those seeking a copy of their credit report successfully answer several multiple choice questions about their financial history. But until the end of 2022, Experian’s website allowed anyone to bypass these questions and go straight to the consumer’s report. All that was needed was the person’s name, address, birthday and Social Security number.

The vulnerability in Experian’s website was exploitable after one applied to see their credit file via annualcreditreport.com.

In December, KrebsOnSecurity heard from Jenya Kushnir, a security researcher living in Ukraine who said he discovered the method being used by identity thieves after spending time on Telegram chat channels dedicated to the cashing out of compromised identities.

“I want to try and help to put a stop to it and make it more difficult for [ID thieves] to access, since [Experian is] not doing shit and regular people struggle,” Kushnir wrote in an email to KrebsOnSecurity explaining his motivations for reaching out. “If somehow I can make small change and help to improve this, inside myself I can feel that I did something that actually matters and helped others.”

Kushnir said the crooks learned they could trick Experian into giving them access to anyone’s credit report, just by editing the address displayed in the browser URL bar at a specific point in Experian’s identity verification process.

Following Kushnir’s instructions, I sought a copy of my credit report from Experian via annualcreditreport.com — a website that is required to provide all Americans with a free copy of their credit report from each of the three major reporting bureaus, once per year.

Annualcreditreport.com begins by asking for your name, address, SSN and birthday. After I supplied that and told Annualcreditreport.com I wanted my report from Experian, I was taken to Experian.com to complete the identity verification process.

Normally at this point, Experian’s website would present four or five multiple-guess questions, such as “Which of the following addresses have you lived at?”

Kushnir told me that when the questions page loads, you simply change the last part of the URL from “/acr/oow/” to “/acr/report,” and the site would display the consumer’s full credit report.

But when I tried to get my report from Experian via annualcreditreport.com, Experian’s website said it didn’t have enough information to validate my identity. It wouldn’t even show me the four multiple-guess questions. Experian said I had three options for a free credit report at this point: Mail a request along with identity documents, call a phone number for Experian, or upload proof of identity via the website.

But that didn’t stop Experian from showing me my full credit report after I changed the Experian URL as Kushnir had instructed — modifying the error page’s trailing URL from “/acr/OcwError” to simply “/acr/report”.

Experian’s website then immediately displayed my entire credit file.

Even though Experian said it couldn’t tell that I was actually me, it still coughed up my report. And thank goodness it did. The report contains so many errors that it’s probably going to take a good deal of effort on my part to straighten out.

Now I know why Experian has NEVER let me view my own file via their website. For example, there were four phone numbers on my Experian credit file: Only one of them was mine, and that one hasn’t been mine for ages.

I was so dumbfounded by Experian’s incompetence that I asked a close friend and trusted security source to try the method on her identity file at Experian. Sure enough, when she got to the part where Experian asked questions, changing the last part of the URL in her address bar to “/report” bypassed the questions and immediately displayed her full credit report. Her report also was replete with errors.

KrebsOnSecurity shared Kushnir’s findings with Experian on Dec. 23, 2022. On Dec. 27, 2022, Experian’s PR team acknowledged receipt of my Dec. 23 notification, but the company has so far ignored multiple requests for comment or clarification.

By the time Experian confirmed receipt of my report, the “exploit” Kushnir said he learned from the identity thieves on Telegram had been patched and no longer worked. But it remains unclear how long Experian’s website was making it so easy to access anyone’s credit report.

In response to information shared by KrebsOnSecurity, Senator Ron Wyden (D-Ore.) said he was disappointed — but not at all surprised — to hear about yet another cybersecurity lapse at Experian.

“The credit bureaus are poorly regulated, act as if they are above the law and have thumbed their noses at Congressional oversight,” Wyden said in a written statement. “Just last year, Experian ignored repeated briefing requests from my office after you revealed another cybersecurity lapse the company.”

Sen. Wyden’s quote above references a story published here in July 2022, which broke the news that identity thieves were hijacking consumer accounts at Experian.com just by signing up as them at Experian once more, supplying the target’s static, personal information (name, DoB/SSN, address) but a different email address.

From interviews with multiple victims who contacted KrebsOnSecurity after that story, it emerged that Experian’s own customer support representatives were actually telling consumers who got locked out of their Experian accounts to recreate their accounts using their personal information and a new email address. This was Experian’s advice even for people who’d just explained that this method was what identity thieves had used to lock them in out in the first place.

Clearly, Experian found it simpler to respond this way, rather than acknowledging the problem and addressing the root causes (lazy authentication and abhorrent account recovery practices). It’s also worth mentioning that reports of hijacked Experian.com accounts persisted into late 2022. That screw-up has since prompted a class action lawsuit against Experian.

Sen. Wyden said the Federal Trade Commission (FTC) and Consumer Financial Protection Bureau (CFPB) need to do much more to protect Americans from screw-ups by the credit bureaus.

“If they don’t believe they have the authority to do so, they should endorse legislation like my Mind Your Own Business Act, which gives the FTC power to set tough mandatory cybersecurity standards for companies like Experian,” Wyden said.

Sadly, none of this is terribly shocking behavior for Experian, which has shown itself a completely negligent custodian of obscene amounts of highly sensitive consumer information.

In April 2021, KrebsOnSecurity revealed how identity thieves were exploiting lax authentication on Experian’s PIN retrieval page to unfreeze consumer credit files. In those cases, Experian failed to send any notice via email when a freeze PIN was retrieved, nor did it require the PIN to be sent to an email address already associated with the consumer’s account.

A few days after that April 2021 story, KrebsOnSecurity broke the news that an Experian API was exposing the credit scores of most Americans.

It’s bad enough that we can’t really opt out of companies like Experian making $2.6 billion each quarter collecting and selling gobs of our personal and financial information. But there has to be some meaningful accountability when these monopolistic companies engage in negligent and reckless behavior with the very same consumer data that feeds their quarterly profits. Or when security and privacy shortcuts are found to be intentional, like for cost-saving reasons.

And as we saw with Equifax’s consolidated class-action settlement in response to letting state-sponsored hackers from China steal data on nearly 150 million Americans back in 2017, class-actions and more laughable “free credit monitoring” services from the very same companies that created the problem aren’t going to cut it.

WHAT CAN YOU DO?

It is easy to adopt a defeatist attitude with the credit bureaus, who often foul things up royally even for consumers who are quite diligent about watching their consumer credit files and disputing any inaccuracies.

But there are some concrete steps that everyone can take which will dramatically lower the risk that identity thieves will ruin your financial future. And happily, most of these steps have the side benefit of costing the credit bureaus money, or at least causing the data they collect about you to become less valuable over time.

The first step is awareness. Find out what these companies are saying about you behind your back. Keep in mind that — fair or not — your credit score as collectively determined by these bureaus can affect whether you get that loan, apartment, or job. In that context, even small, unintentional errors that are unrelated to identity theft can have outsized consequences for consumers down the road.

Each bureau is required to provide a free copy of your credit report every year. The easiest way to get yours is through annualcreditreport.com.

Some consumers report that this site never works for them, and that each bureau will insist they don’t have enough information to provide a report. I am definitely in this camp. Thankfully, a financial institution that I already have a relationship with offers the ability to view your credit file through them. Your mileage on this front may vary, and you may end up having to send copies of your identity documents through the mail or website.

When you get your report, look for anything that isn’t yours, and then document and file a dispute with the corresponding credit bureau. And after you’ve reviewed your report, set a calendar reminder to recur every four months, reminding you it’s time to get another free copy of your credit file.

If you haven’t already done so, consider making 2023 the year that you freeze your credit files at the three major reporting bureaus, including Experian, Equifax and TransUnion. It is now free to people in all 50 U.S. states to place a security freeze on their credit files. It is also free to do this for your partner and/or your dependents.

Freezing your credit means no one who doesn’t already have a financial relationship with you can view your credit file, making it unlikely that potential creditors will grant new lines of credit in your name to identity thieves. Freezing your credit file also means Experian and its brethren can no longer sell peeks at your credit history to others.

Anytime you wish to apply for new credit or a new job, or open an account at a utility or communications provider, you can quickly thaw a freeze on your credit file, and set it to freeze automatically again after a specified length of time.

Please don’t confuse a credit freeze (a.k.a. “security freeze”) with the alternative that the bureaus will likely steer you towards when you ask for a freeze: “Credit lock” services.

The bureaus pitch these credit lock services as a way for consumers to easily toggle their credit file availability with push of a button on a mobile app, but they do little to prevent the bureaus from continuing to sell your information to others.

My advice: Ignore the lock services, and just freeze your credit files already.

One final note. Frequent readers here will have noticed that I’ve criticized these so-called “knowledge-based authentication” or KBA questions that Experian’s website failed to ask as part of its consumer verification process.

KrebsOnSecurity has long assailed KBA as weak authentication because the questions and answers are drawn largely from consumer records that are public and easily accessible to organized identity theft groups.

That said, given that these KBA questions appear to be the ONLY thing standing between me and my Experian credit report, it seems like maybe they should at least take care to ensure that those questions actually get asked.