High severity7.0NVD Advisory· Published Nov 9, 2026

CVE-2026-125257

Description

FFmpeg through 9.0.2 contains an off-by-one heap overflow vulnerability in get_exponent_dynamic() in libavcodec/nellymoserenc.c that allows writing one element past the opt and path allocations. Attackers can supply crafted audio to applications encoding Nellymoser with trellis enabled, causing idx to equal OPT_SIZE and overwrite adjacent heap memory.

AI Insight

LLM-synthesized narrative grounded in this CVE's description and references.

Affected products

FFmpeg/Ffmpegllm-fuzzy
Range: <=9.0.2

Patches

Vulnerability mechanics

References

code.ffmpeg.org/FFmpeg/FFmpeg/pulls/24471nvd
github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/nellymoserenc.cnvd
github.com/FFmpeg/FFmpeg/commit/733bec3e19759520ccdbeb6c3c0cae280bbe6dc5nvd
www.vulncheck.com/advisories/ffmpeg-through-9.0.2-heap-overflow-via-nellymoser-encoder-trellis-searchnvd

News mentions

No linked articles in our index yet.

cvss	0.455
epss	0.000
exploit	0.000
kev	0.000
patch	-0.070
ransomware	0.000