CVE-2026-125246

medium

Description

FFmpeg through 9.0.2 contains a denial of service vulnerability in cbs_jpeg_assemble_fragment() that miscounts 0xff stuffing bytes in JPEG scan headers. Attackers can supply a crafted JPEG/MJPEG stream with 0xff in the scan header, triggering an av_assert0 abort when CBS-based bitstream filters process it.

References

https://www.vulncheck.com/advisories/ffmpeg-through-9.0.2-assertion-failure-dos-via-cbs-jpeg-assemble-fragment

https://github.com/FFmpeg/FFmpeg/commit/ee457fdcdb3a069ef35910a2e1cacff10906b131

https://github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/cbs_jpeg.c#L365

https://github.com/FFmpeg/FFmpeg

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-120196

https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/25232

Details

Source: Mitre, NVD

Published: 2026-11-09

Updated: 2026-11-10

Risk Information

CVSS v2

Base Score: 4

Vector: CVSS2#AV:L/AC:H/Au:N/C:N/I:N/A:C

Severity: Medium

CVSS v3

Base Score: 4.7

Vector: CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:H

Severity: Medium

CVSS v4

Base Score: 5.7

Vector: CVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Severity: Medium

EPSS

EPSS: 0.00156