CVE-2026-125226

medium

Description

FFmpeg through 9.0.2 contains an uncontrolled memory allocation vulnerability in sbg_read_header() in libavformat/sbgdec.c that derives an unbounded default frame size from the script's sample rate. Attackers can supply a crafted SBaGen script declaring a very high -r sample rate so the wavesynth decoder allocates enormous audio frames, exhausting memory and causing denial of service.

References

https://www.vulncheck.com/advisories/ffmpeg-through-9.0.2-excessive-memory-allocation-via-sbagen-demuxer

https://github.com/FFmpeg/FFmpeg/commit/1f4b2e22cfba19f94489ec4a17130f4f0d5d8a0c

https://github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavformat/sbgdec.c#L1419

https://github.com/FFmpeg/FFmpeg

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-120176

https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/25703

Details

Source: Mitre, NVD

Published: 2026-11-09

Updated: 2026-11-10

Risk Information

CVSS v2

Base Score: 4.9

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

Severity: Medium

CVSS v3

Base Score: 5.5

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

Severity: Medium

CVSS v4

Base Score: 6.8

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

Severity: Medium

EPSS

EPSS: 0.00165