CVE-2026-125101

Description

FFmpeg through 9.0.2 contains an information disclosure vulnerability in the VMnc decoder in libavcodec/vmnc.c that restores an unwritten cursor save area into later frames. Attackers can supply a crafted VMnc stream where a frame fails after loading a cursor shape, causing uninitialized heap bytes from screendta to appear in decoded output.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

References

• https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/25716 ↗
• https://github.com/FFmpeg/FFmpeg/commit/50865f20b1f474e6b11735c88f668751bc9aa528 ↗
• https://github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/vmnc.c#L348 ↗
• https://github.com/FFmpeg/FFmpeg ↗
• https://www.vulncheck.com/advisories/ffmpeg-through-9.0.2-vmnc-decoder-uninitialized-heap-memory-disclosure ↗