CVE-2026-120247
FFmpeg 2.3 through 9.0.2 Huffyuv Decoder Uninitialized Heap Memory Disclosure
What happened?
FFmpeg 2.3 through 9.0.2 contains a use of uninitialized resource vulnerability in the Huffyuv decoder that allows attackers to leak heap memory into decoded pixels via short packed-BGR bitstreams. Attackers can craft a Huffyuv BGR24/BGRA video whose entropy data ends early, causing decode_slice() to add uninitialized s->temp[0] bytes into output frames, exposing heap contents.
Affected software and versions
| Software | Version information | Fixed version |
|---|---|---|
| FFmpegFFmpeg | affected: 2.3 to ≤ 9.0.2 | See vendor advisory |
Version information comes from the source record and can include unaffected products and exceptions. Distribution packages may contain backported fixes: an older upstream version alone does not prove a server is affected.
Is it being exploited?
This CVE was not listed in the CISA catalogue at our last retrieval. This does not establish that exploitation is absent.
How to respond
- Confirm the product, installed package version, and any configuration requirements in the vendor advisory.
- Follow the vendor’s remediation or workaround guidance in the references below. Structured fixed-version data is unavailable here; the publisher’s description may include a fix or workaround.
- Restart affected services if required, then verify the running version. Known exploitation may warrant investigation as well as patching.
Sources and remediation references
- https://www.cve.org/CVERecord?id=CVE-2026-120247
- https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/24869
- https://github.com/FFmpeg/FFmpeg/commit/7c73707355708c846f718cca90096bc1a33c8989
- https://github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/huffyuvdec.c#L802
- https://github.com/FFmpeg/FFmpeg
- https://www.vulncheck.com/advisories/ffmpeg-2.3-through-9.0.2-huffyuv-decoder-uninitialized-heap-memory-disclosure