On the sixth day of Christmas, an X account gave to me: a fake 7-Zip ACE - The Record from Recorded Future News

The latest news on the 7-Zip zero-day exploit in December 2024 involves a critical vulnerability that has been publicly disclosed. Here are the key points:

1. Vulnerability Disclosure:

   • A zero-day (0day) vulnerability in 7-Zip, a widely-used file archiving tool, has been disclosed by an individual using the alias "NSA_Employee39" on December 30, 202425.
   • The vulnerability exploits 7-Zip's ACE format and leverages a malformed LZMA stream to trigger a buffer overflow in the RC_NORM function, allowing attackers to execute arbitrary code2.

2. Implications:

   • This exploit enables attackers to craft malicious .7z files that can infect a user's system simply by opening or extracting the file, without requiring further interaction2.
   • The potential for exploitation extends beyond individual users, as organizations often automate workflows involving file extraction, making it a significant risk for supply chains2.

3. Mitigation Strategies:

   • Users and organizations are advised to monitor for updates and apply them promptly. Implementing controls to scrutinize and sandbox third-party files before processing is also recommended2.
   • Educating users about the risks of opening unsolicited or suspicious archive files is crucial. Additionally, researchers and cybersecurity professionals must collaborate to investigate and mitigate emerging threats tied to this exploit2.

4. Author's Dispute:

   • The author of 7-Zip has disputed the legitimacy of the reported 0-day vulnerability, and the article will be updated as more information becomes available2.

5. Related Threats:

   • The same hacker hinted at releasing another zero-day vulnerability targeting MyBB, an open-source forum software, which could pave the way for massive breaches and database leaks across online communities2.

In summary, the 7-Zip zero-day exploit is a critical vulnerability that has been publicly disclosed, posing significant risks for both individual users and organizations. Immediate action to patch and mitigate this vulnerability is essential to prevent potential attacks.