Former NSA hacker reversed Kaspersky Lab antivirus to compose signatures capable of detecting classified documents

Former NSA hacker, demonstrated how to subvert the Kaspersky Lab antivirus and turn it into a powerful search tool for classified documents.

The Kaspersky case demonstrated that security software can be exploited by intelligence agencies as a powerful spy tool.

Patrick Wardle, chief research officer at Digita Security and former NSA hacker, demonstrated it by subverting the Kaspersky Lab antivirus and turning it into a powerful search tool for classified documents.

“In the battle against malicious code, antivirus products are a staple,” Patrick Wardle told the New York Times. “Ironically, though, these products share many characteristics with the advanced cyberespionage collection implants they seek to detect.”

“I wanted to know if this was a feasible attack mechanism,” Mr. Wardle added. “I didn’t want to get into the complex accusations. But from a technical point of view, if an antivirus maker wanted to, was coerced to, or was hacked or somehow subverted, could it create a signature to flag classified documents?”

In December, US President Donald Trump signed a bill that bans the use of Kaspersky Lab products and services in federal agencies.

According to a draft of a top-secret report leaked by Edward J. Snowden, the NSA at least since 2008 was targeting antivirus software (i.e. Checkpoint and Avast) to collect sensitive information stored in the target machines.

Mr. Wardle conducted a reverse-engineering of Kaspersky Lab antivirus software to explore the possibility to abuse it for intelligence purposes. The expert’s goal was to compose a signature that is able to detect classified documents.

Mr. Wardle discovered that the code incredibly complex, unlike traditional antivirus software, Kaspersky’s malware signatures are easily updated. This feature can be tweaked to automatically scan the victim’s machine and steal classified documents.

“Modern anti-virus products are incredibly complex pieces of software and Kaspersky is likely one of the most complex. Thus, merely gaining a reasonable understanding of its signatures and scanning logic is a challenging task.” wrote Wardle

“Though the installer ships with built-in signatures, as is the case with any anti-virus program, Kaspersky’s anti-virus engine regularly checks for, and automatically installs any new signatures” “When new signatures are available, they are downloaded by the kav daemon from Kaspersky’s update servers”

Wardle found antivirus scanning could be the used for cyberespionage activities.

The expert pointed out that officials routinely classify top secret documents with the marking “TS/SCI,” (“Top Secret/Sensitive Compartmented Information),” then he added a rule to Kaspersky’s antivirus program to flag any documents that contained the “TS/SCI” marker.

To test the new rule, the researcher edited a document on his computer containing text from the Winnie the Pooh children’s book series and added “TS/SC” marker.

Kaspersky antivirus

As soon as the Winnie the Pooh document was saved to his machine, the Kaspersky’s antivirus software flagged and quarantined the document.

The successive phase of Wardle’s test was on discovering how flagged documents are managed, but it normal that an antivirus software send data back to the company for further analysis.

Kaspersky Lab explained that Wardle’s research is not corrected because the company is not able to deliver a specific signature or update to only one user in a stealthy way.

“It is impossible for Kaspersky Lab to deliver a specific signature or update to only one user in a secret, targeted way because all signatures are always openly available to all our users; and updates are digitally signed, further making it impossible to fake an update,” Kaspersky said in a statement.

Anyway, Wardle’s research demonstrated that hacking vendor’s platforms it is possible to use the antivirus as a search tool.

“However, a malicious or willing insider within any anti-virus company, who could tactically deployed such a signature, would likely remain undetected. And of course, in a hypothetical scenario; any anti-virus company that is coerced to, or is willing to work with a larger entity (such as a governemnt) would equally be able to stealthily leverage their product to detect and exfilitrate any files of interest.” concluded the expert.
“Sometimes the line between what is good and evil, comes down to a signal signature… “


Pierluigi Paganini

(Security Affairs – Kaspersky Lab Antivirus, hacking)



The post Former NSA hacker reversed Kaspersky Lab antivirus to compose signatures capable of detecting classified documents appeared first on Security Affairs.

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