What is CVE-2026-125073?

CVE-2026-125073 is a medium-severity vulnerability in Ffmpeg, classified under Loop with Unreachable Exit Condition (Infinite Loop). CVSS score: 5.5/10. Published 2026-11-09.

How severe is CVE-2026-125073?

Medium severity. CVSS v3 base score is 5.5 out of 10.

Vulnerability in Ffmpeg

CVE-2026-125073

FFmpeg through 9.0.2 contains an infinite loop vulnerability in bit_allocation() in libavcodec/imc.c that allows attackers to hang decoding by supplying audio blocks with a negative bit budget. Attackers can craft IMC or IAC audio files that drive freebits negative, causing the reduction loop to never terminate and consuming 100% CPU.

Published 2026-11-09.

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Ffmpeg

Weakness classification (CWE)

CWE-835 — Loop with Unreachable Exit Condition (Infinite Loop)

References

code.ffmpeg.org/FFmpeg/FFmpeg/pulls/25696 (issue-tracking)
github.com/FFmpeg/FFmpeg (product)
github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/imc.c (technical-description)
Patch Commit (patch)
VulnCheck Advisory: FFmpeg through 9.0.2 Infinite Loop Denial of Service via IMC/IAC Decoder (third-party-advisory)

Frequently asked questions

What is CVE-2026-125073?: CVE-2026-125073 is a medium-severity vulnerability in Ffmpeg, classified under Loop with Unreachable Exit Condition (Infinite Loop). CVSS score: 5.5/10. Published 2026-11-09.
How severe is CVE-2026-125073?: Medium severity. CVSS v3 base score is 5.5 out of 10.