CVSS 4.0
4.8 mediumCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:NCVE-2026-125177 FFmpeg through 9.0.2 Uninitialized Heap Memory Disclosure via MSCC/SRGC Decoder
Medium (4.8) in ffmpeg ffmpeg. EPSS 0.1% estimated probability of exploitation activity in the next 30 days.
On this page
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.
Severity
CVSS 3.1
3.3 lowCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N- EPSS
- 0.1% estimated probability of exploitation activity in the next 30 days; 3rd percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
- CISA's assessment (SSVC)
- Exploitation: none · Automatable: no · Technical impact: partial, assessed 2026-11-14. From CISA's Vulnrichment in the CVE List: whether it is exploited, whether exploiting it can be automated, and how much control it gives.
- CWE
- CWE-908 Use of Uninitialized Resource
- Published
- Modified
- Assigned by
- VulnCheck (CNA)
- NVD analysis
- Under analysis
- Record from
- the NVD, synced
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Affected
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| FFmpeg | through 9.0.2 |
Linux distributions
| Distribution | Release | Package | Fixed in | Advisory |
|---|---|---|---|---|
| Ubuntu | 26.10, Pro:16.04:LTS, Pro:18.04:LTS and 4 more | ffmpeg | no fix listed | UBUNTU-CVE-2026-125177 |
From the distributions' data via OSV.dev: Ubuntu Security Notices © Canonical Ltd., CC BY-SA 4.0. Modified: reformatted and linked to CVE records. Credits. On the distributions' own pages: Ubuntu.
References
- https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/24465
- https://github.com/FFmpeg/FFmpeg
- https://github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/mscc.c#L236
- https://github.com/FFmpeg/FFmpeg/commit/263a85e2a2127396f8a2b0c329ec798e1ea015ad
- https://www.vulncheck.com/advisories/ffmpeg-through-9.0.2-uninitialized-heap-memory-disclosure-via-mscc-srgc-decoder