Russias Ukraine Invasion Takes A Bleak Turn As Hackers Unleash Devastating Cyberattack Exploiting 7-Zip Zero-Day

Russia’s Ongoing Invasion of Ukraine Takes a Darker Turn as 7-Zip Zero-Day Exploited by Sophisticated Hackers

A recent discovery has shed light on the cunning tactics employed by Russian cybercrime groups in their ongoing invasion of Ukraine, exploiting a zero-day vulnerability in the widely-used 7-Zip archiving utility. The vulnerability, tracked as CVE-2025-0411, allows hackers to bypass Windows protections, including the MotW (Mark of the Web) defense mechanism designed to limit the execution of files downloaded from the internet or networked shares.

The MotW defense is a crucial layer of protection, working by placing a “Zone.Identifier” tag on all files downloaded from the internet or networked shares. This tag subjects the file to additional scrutiny from Windows Defender SmartScreen and restrictions on how or when it can be executed. However, researchers at Trend Micro have found that prior to version 24.09, 7-Zip failed to properly propagate MoTW protections to the content of double-encapsulated archives, leaving users vulnerable to attacks.

In a cleverly crafted exploit, hackers embedded an executable file within an archive and then embedded the archive into another archive. The outer archive carried the MotW tag, while the inner one did not. This allowed the hackers to bypass Windows protections, effectively turning their own files against them. The vulnerability was fixed with the release of version 24.09 in late November, but not before it had been actively exploited by sophisticated hackers.

The discovery of CVE-2025-0411 highlights the importance of timely software updates and the need for users to stay vigilant against evolving cyber threats. According to Peter Girnus, a researcher at Trend Micro, “the root cause of CVE-2025-0411 is that prior to version 24.09, 7-Zip did not properly propagate MoTW protections to the content of double-encapsulated archives.” This vulnerability serves as a stark reminder that even seemingly innocuous software can be used as a means to launch devastating attacks.

Sophisticated hacking groups have long utilized zero-day exploits like CVE-2025-0411 to gain an upper hand in the digital battlefield. As the conflict in Ukraine continues, it is essential for users to stay informed about emerging threats and take steps to protect themselves against such attacks.