Category: forensics

Interesting forensics in connection with a serial killer arrest:

Investigators went through phone records collected from both midtown Manhattan and the Massapequa Park area of Long Island—two areas connected to a “burner phone” they had tied to the killings. (In court, prosecutors later said the burner phone was identified via an email account used to “solicit and arrange for sexual activity.” The victims had all been Craigslist escorts, according to officials.)

They then narrowed records collected by cell towers to thousands, then to hundreds, and finally down to a handful of people who could match a suspect in the killings.

From there, authorities focused on people who lived in the area of the cell tower and also matched a physical description given by a witness who had seen the suspected killer.

In that narrowed pool, they searched for a connection to a green pickup truck that a witness had seen the suspect driving, the sources said.

Investigators eventually landed on Heuermann, who they say matched a witness’ physical description, lived close to the Long Island cell site and worked near the New York City cell sites that captured the other calls.

They also learned he had often driven a green pickup truck, registered to his brother, officials said. But they needed more than just circumstantial evidence.

Investigators were able to obtain DNA from an immediate family member and send it to a specialized lab, sources said. According to the lab report, Heuermann’s family member was shown to be related to a person who left DNA on a burlap sack containing one of the buried victims.

There’s nothing groundbreaking here; it’s casting a wide net with cell phone geolocation data and then winnowing it down using other evidence and investigative techniques. And right now, those are expensive and time consuming, so only used in major crimes like murder (or, in this case, murders).

What’s interesting to think about is what happens when this kind of thing becomes cheap and easy: when it can all be done through easily accessible databases, or even when an AI can do the sorting and make the inferences automatically. Cheaper digital forensics means more digital forensics, and we’ll start seeing this kind of thing for even routine crimes. That’s going to change things.

Don’t do it:

Recently, the manager of the Harvard Med School morgue was accused of stealing and selling human body parts. Cedric Lodge and his wife Denise were among a half-dozen people arrested for some pretty grotesque crimes. This part is also at least a little bit funny though:

Over a three-year period, Taylor appeared to pay Denise Lodge more than $37,000 for human remains. One payment, for $1,000 included the memo “head number 7.” Another, for $200, read “braiiiiiins.”

It’s so easy to think that you won’t get caught.

The New York Times has a long article on the investigative techniques used to identify the person who stabbed and killed four University of Idaho students.

Pay attention to the techniques:

The case has shown the degree to which law enforcement investigators have come to rely on the digital footprints that ordinary Americans leave in nearly every facet of their lives. Online shopping, car sales, carrying a cellphone, drives along city streets and amateur genealogy all played roles in an investigation that was solved, in the end, as much through technology as traditional sleuthing.

[…]

At that point, investigators decided to try genetic genealogy, a method that until now has been used primarily to solve cold cases, not active murder investigations. Among the growing number of genealogy websites that help people trace their ancestors and relatives via their own DNA, some allow users to select an option that permits law enforcement to compare crime scene DNA samples against the websites’ data.

A distant cousin who has opted into the system can help investigators building a family tree from crime scene DNA to triangulate and identify a potential perpetrator of a crime.

[…]

On Dec. 23, investigators sought and received Mr. Kohberger’s cellphone records. The results added more to their suspicions: His phone was moving around in the early morning hours of Nov. 13, but was disconnected from cell networks ­- perhaps turned off—in the two hours around when the killings occurred.

Kaspersky is reporting a zero-click iOS exploit in the wild:

Mobile device backups contain a partial copy of the filesystem, including some of the user data and service databases. The timestamps of the files, folders and the database records allow to roughly reconstruct the events happening to the device. The mvt-ios utility produces a sorted timeline of events into a file called “timeline.csv,” similar to a super-timeline used by conventional digital forensic tools.

Using this timeline, we were able to identify specific artifacts that indicate the compromise. This allowed to move the research forward, and to reconstruct the general infection sequence:

  • The target iOS device receives a message via the iMessage service, with an attachment containing an exploit.
  • Without any user interaction, the message triggers a vulnerability that leads to code execution.
  • The code within the exploit downloads several subsequent stages from the C&C server, that include additional exploits for privilege escalation.
  • After successful exploitation, a final payload is downloaded from the C&C server, that is a fully-featured APT platform.
  • The initial message and the exploit in the attachment is deleted

The malicious toolset does not support persistence, most likely due to the limitations of the OS. The timelines of multiple devices indicate that they may be reinfected after rebooting. The oldest traces of infection that we discovered happened in 2019. As of the time of writing in June 2023, the attack is ongoing, and the most recent version of the devices successfully targeted is iOS 15.7.

No attribution as of yet.

The Intercept has a long article on the insecurity of photo cropping:

One of the hazards lies in the fact that, for some of the programs, downstream crop reversals are possible for viewers or readers of the document, not just the file’s creators or editors. Official instruction manuals, help pages, and promotional materials may mention that cropping is reversible, but this documentation at times fails to note that these operations are reversible by any viewers of a given image or document.

[…]

Uncropped versions of images can be preserved not just in Office apps, but also in a file’s own metadata. A photograph taken with a modern digital camera contains all types of metadata. Many image files record text-based metadata such as the camera make and model or the GPS coordinates at which the image was captured. Some photos also include binary data such as a thumbnail version of the original photo that may persist in the file’s metadata even after the photo has been edited in an image editor.