# CVE-2026-75142: FFmpeg Stack Buffer Overflow in MPEG-PS Muxer via mpegenc.c

> A stack buffer overflow in FFmpeg's MPEG-PS muxer allows attackers to execute arbitrary code or cause denial of service via crafted media files.

- **Severity:** High 8.5 (`CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 19 Aug 2026
- **Updated:** 27 Oct 2026
- **Also known as:** DEBIAN-CVE-2026-75142, ECHO-8340-2df2-4096, GHSA-5vj8-jgqj-77h6, UBUNTU-CVE-2026-75142

## What is CVE-2026-75142?

CVE-2026-75142 is a high-severity memory corruption vulnerability in FFmpeg, published on 19 Aug 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

### Official description

FFmpeg before commit 9d786e4 contains a stack buffer overflow in the MPEG-PS muxer (libavformat/mpegenc.c). When muxing input with more streams than the muxer's fixed-size stack buffer accommodates, the buffer is overflowed. A crafted input with an excessive number of streams triggers the overflow during MPEG-PS muxing.

Weakness: CWE-121 (Stack-based Buffer Overflow)

## Which versions are affected by CVE-2026-75142?


## How do I fix CVE-2026-75142?

Apply the vendor's patch.

## Is CVE-2026-75142 being exploited?

There is no known exploitation of CVE-2026-75142 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-75142 and fix it if it is affected.

What it is: CVE-2026-75142 is a high-severity memory corruption vulnerability in FFmpeg, published on 19 Aug 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-75142 in the wild and no public exploit code.

Affected product: FFmpeg. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-75142/ (Markdown: https://insights.sbomify.com/CVE-2026-75142/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-75142
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-75142
- OSV: https://osv.dev/vulnerability/CVE-2026-75142

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-75142/
Summaries are generated and may contain mistakes; the official description above is the record.