# CVE-2026-64835: FFmpeg OOB memory access in ADX audio decoder

Source: https://junglewise.ai/threats/cve-2026-64835-ffmpeg-oob-memory-access-in-adx-audio-decoder  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-22. Updated: 2026-07-22  
License: CC BY 4.0 with a link back

CVE-2026-64835 · Severity: high · CVSS 8.8 · Published 2026-07-22

FFmpeg, a widely used multimedia framework for processing audio and video, contains a flaw in its ADX audio decoder. By tricking a user into opening a specially crafted audio file, an attacker could cause the application to crash or potentially execute unauthorized code. This could lead to a total compromise of the system running the affected software or the theft of sensitive user data.

Technologies: [Ffmpeg](https://junglewise.ai/threats/technologies/ffmpeg). Vendors: [Ffmpeg](https://junglewise.ai/threats/vendors/ffmpeg).

## Quick answers

**Is CVE-2026-64835 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-64835 being exploited in the wild.

**How severe is CVE-2026-64835?** High severity, with a CVSS score of 8.8, published 22 July 2026.

**Which products and versions are affected?** Ffmpeg 4.4 through 8.1.2.

**Is there a fix for CVE-2026-64835?** A patch was published on 2026-07-02: Pull request merged into master branch Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-64835 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-64835?** Check whether you run Ffmpeg at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

An out-of-bounds (OOB) memory access vulnerability exists in the FFmpeg ADX audio decoder (libavcodec/adxdec.c). The root cause is a failure to update the internal channel state in the adx_decode_frame function when AV_PKT_DATA_NEW_EXTRADATA side data is received mid-stream. While the function re-parses the stream header, it retains a stale channel count, leading subsequent decoding operations to access the prev[] state array out of bounds. An attacker can exploit this by providing a crafted ADX or AAX file with a mid-stream channel layout change, potentially achieving remote code execution or a denial-of-service. A fix has been committed to the FFmpeg master branch.

## Affected products

- FFmpeg FFmpeg 4.4 through 8.1.2

## Timeline

- 2026-06-29: other: Fix committed to FFmpeg source code
- 2026-07-02: patched: Pull request merged into master branch
- 2026-07-22: advisory: NVD and VulnCheck published advisory details

## References

- [https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/1836ef96846937a6cc2443698a693104f5c0b21e](https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/1836ef96846937a6cc2443698a693104f5c0b21e)
- [https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/23659](https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/23659)
- [https://www.vulncheck.com/advisories/ffmpeg-out-of-bounds-memory-access-in-adx-audio-decoder](https://www.vulncheck.com/advisories/ffmpeg-out-of-bounds-memory-access-in-adx-audio-decoder)

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