# CVE-2026-70629: FFmpeg 3.0 < 9.0 Uninitialized Heap Memory Read in RSCC Decoder

> Attackers can disclose heap memory contents by supplying a crafted video file to FFmpeg's RSCC decoder, potentially exposing sensitive data from prior allocations.

- **Severity:** Medium 6.8 (`CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:N/VA:N/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:** 6 Aug 2026
- **Updated:** 14 Aug 2026
- **Also known as:** DEBIAN-CVE-2026-70629, ECHO-6986-2e97-593f, GHSA-824f-v6qw-342h, JLSEC-2026-1189, OESA-2026-3467, OESA-2026-3471, UBUNTU-CVE-2026-70629

## What is CVE-2026-70629?

CVE-2026-70629 is a medium-severity vulnerability in Ffmpeg Ffmpeg, published on 6 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 versions from 3.0 up to, but not including, 9.0 contain an uninitialized heap memory read vulnerability in the native RSCC decoder (libavcodec/rscc.c) that allows attackers to disclose heap memory contents by supplying a crafted video file with a compressed tile that decompresses fewer bytes than the declared tile geometry requires. When rscc_decode_frame() calls av_image_copy_plane() without validating the decompressed byte count against the tile dimensions, the unwritten suffix of the persistent intermediate buffer ctx->inflated_buf is copied into the decoded frame, potentially exposing data from prior heap allocations or previous decoded frames in persistent decoding services.

Weakness: CWE-908 (Use of Uninitialized Resource)

## Which versions are affected by CVE-2026-70629?

It affects 1 product.


Products: Ffmpeg Ffmpeg.

## How do I fix CVE-2026-70629?

Upgrade to a fixed version.

## Is CVE-2026-70629 being exploited?

There is no known exploitation of CVE-2026-70629 in the wild and no public exploit code.

## Other vulnerabilities in Ffmpeg Ffmpeg

- [CVE-2013-0864](https://insights.sbomify.com/CVE-2013-0864/): Memory corruption in n/a (critical 10.0)
- [CVE-2013-0872](https://insights.sbomify.com/CVE-2013-0872/): Memory corruption in n/a (critical 10.0)
- [CVE-2013-0873](https://insights.sbomify.com/CVE-2013-0873/): Memory corruption in n/a (critical 10.0)
- [CVE-2013-4265](https://insights.sbomify.com/CVE-2013-4265/): Null dereference in n/a (critical 10.0)
- [CVE-2011-3937](https://insights.sbomify.com/CVE-2011-3937/): Memory corruption in n/a (critical 10.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-70629 and fix it if it is affected.

What it is: CVE-2026-70629 is a medium-severity vulnerability in Ffmpeg Ffmpeg, published on 6 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-2026-70629 in the wild and no public exploit code.

Affected product: Ffmpeg 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-2026-70629/ (Markdown: https://insights.sbomify.com/CVE-2026-70629/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-70629
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-70629
- OSV: https://osv.dev/vulnerability/CVE-2026-70629

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From sbomify Insights: https://insights.sbomify.com/CVE-2026-70629/
Summaries are generated and may contain mistakes; the official description above is the record.