UBUNTU-CVE-2026-120243: Medium severity ubuntu/libav vulnerability
FFmpeg 2.0 through 9.0.2 contains a use of uninitialized variable vulnerability in the Go2Meeting decoder that allows attackers to leak stack memory through out-of-range palette indices. Attackers can craft a G2M3/G2M4 stream with a short Kempf palette so kempfrestorebuf() copies uninitialized stack bytes, including pointers or stack guards, into decoded output.
Affected Software
Event History
Frequently Asked Questions
Which deployments should be prioritized for review?
Review Ubuntu systems using the ffmpeg or libav packages where G2M3 or G2M4 media may be decoded, particularly if users can open media from untrusted sources. The affected FFmpeg range is 2.0 through 9.0.2.
What conditions are required for exploitation?
An attacker must provide a crafted G2M3 or G2M4 stream containing a short Kempf palette and have it decoded. The CVSS vector indicates no attacker privileges are required, but user interaction is required and the attack is local.
What is the expected impact if exploited?
The issue can disclose uninitialized stack memory through decoded output, potentially including pointers or stack guards. The reported impact is confidentiality loss; integrity and availability impacts are rated none.