Is there a public exploit for CVE-2026-125257?

No public exploit for CVE-2026-125257 was found in Exploit-DB, Metasploit, Nuclei templates or public proof-of-concept repositories. That is an absence of evidence rather than proof that none exists.

How severe is CVE-2026-125257?

CVE-2026-125257 scores CVSS 7.3 (v4.0), rated high.

What does CVE-2026-125257 affect?

CVE-2026-125257 affects FFMPEG FFmpeg.

7.3 High

FFmpeg through 9.0.2 contains an off-by-one heap overflow vulnerability in getexponentdynamic() in libavcodec/nellymoserenc.c that allows…

CVE-2026-125257

FFmpeg through 9.0.2 contains an off-by-one heap overflow vulnerability in getexponentdynamic() 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 OPTSIZE and overwrite adjacent heap memory.

Assessment

CVSS: 7.3 (v4.0)
Severity: High
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 9 November 2026
Last updated: 9 November 2026
Affected: FFMPEG · FFmpeg
Assigner: VulnCheck

CVSS vectorCVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

At the source

EUVD (ENISA)

References

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