Vulnerability in Ffmpeg
CVE-2026-125177
FFmpeg through 9.0.2 contains an information disclosure vulnerability in the MSCC/SRGC decoder in libavcodec/mscc.c that outputs uninitialized heap bytes when RLE data ends early. Attackers can craft an MSCC or SRGC stream, such as in AVI, whose RLE data terminates early so the decoded frame exposes leftover heap memory to viewers of the output.
Published .
CVSS v3 metric
CVSS v3 base score 3.3 (Low). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N.
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
Weakness classification (CWE)
References
- code.ffmpeg.org/FFmpeg/FFmpeg/pulls/24465 (issue-tracking)
- github.com/FFmpeg/FFmpeg (product)
- github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/mscc.c (technical-description)
- github.com/FFmpeg/FFmpeg/commit/263a85e2a2127396f8a2b0c329ec798e1ea015ad (patch)
- www.vulncheck.com/advisories/ffmpeg-through-9.0.2-uninitialized-heap-memory-dis… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-125177?
- CVE-2026-125177 is a low-severity vulnerability in Ffmpeg, classified under Use of Uninitialized Resource. CVSS score: 3.3/10. Published 2026-11-09.
- How severe is CVE-2026-125177?
- Low severity. CVSS v3 base score is 3.3 out of 10.