Heap Buffer Overflow in FFmpeg's cbs_jpeg_write_scan Function
CVE-2026-125227

7.3HIGH

Key Information:

Vendor

Ffmpeg

Status
Ffmpeg
Vendor
CVE Published:
9 November 2026

What is CVE-2026-125227?

FFmpeg versions up to 9.0.2 are affected by an integer overflow vulnerability in the cbs_jpeg_write_scan() function within libavcodec/cbs_jpeg.c. This flaw allows attackers to create harmful MJPEG/JPEG streams that, when processed by specific CBS bitstream filters, can lead to a heap buffer overflow in 32-bit builds. By supplying a crafted scan of 512 MiB or larger, malicious actors can potentially corrupt the heap or crash the application, posing significant risks to system stability.

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/b89ce54d93bf64443...
patch
https://github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/c...
technical-description

CVSS V4

Score:
7.3
Severity:
HIGH
Confidentiality:
High
Integrity:
High
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)
Joshua Rogers
.