Integer Overflow Vulnerability in FFmpeg Affects VP9 Processing
CVE-2026-125253

5.8MEDIUM

Key Information:

Vendor

Ffmpeg

Status
Ffmpeg
Vendor
CVE Published:
9 November 2026

What is CVE-2026-125253?

FFmpeg, prior to version 9.0.2, is susceptible to an integer overflow vulnerability in the function cbs_vp9_split_fragment() found in libavcodec/cbs_vp9.c. This vulnerability allows an attacker to craft a malicious VP9 packet that includes a falsified superframe index with extremely large frame sizes, leading to out-of-bounds read conditions that can crash 32-bit applications. The flaw occurs due to inadequate checks on superframe sizes, allowing values near 2^32 to bypass normal processing limits.

Affected Version(s)

FFmpeg 0 <= 9.0.2

References

https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/25232
issue-tracking
https://github.com/FFmpeg/FFmpeg/commit/6280907da48c4dd78...
patch
https://github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/c...
technical-description

CVSS V4

Score:
5.8
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
None
Availability:
High
Attack Vector:
Local
Attack Complexity:
High
Attack Required:
Physical
Privileges Required:
Undefined
User Interaction:
Unknown

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Joshua Rogers (AISLE Research)
Michael Niedermayer
.