CVE-2026-125175 FFmpeg through 9.0.2 Information Disclosure via Flash Screen Video Decoder

Medium 4.8 Published 9 Nov 2026 Updated 10 Nov 2026

Exploited in the wild: Not known
Fix: None listed

What is CVE-2026-125175?

CVE-2026-125175 is a medium-severity vulnerability in FFmpeg, published on 9 Nov 2026.

Official description

FFmpeg through 9.0.2 contains an information disclosure vulnerability in flashsv_decode_block() in libavcodec/flashsv.c that copies uninitialized heap memory into decoded frames when inflate output is short. Attackers can supply a crafted FLV with an FSV1 stream whose zlib block data decompresses short, then recover heap contents from the decoded or re-encoded output.

Weakness: CWE-908

Which versions are affected by CVE-2026-125175?

How do I fix CVE-2026-125175?

No fix has been published for CVE-2026-125175 yet. Limit exposure of the affected software until one is available.

Is CVE-2026-125175 being exploited?

There is no known exploitation of CVE-2026-125175 in the wild and no public exploit code.

Sources

Also known as GHSA-q8wv-cvjv-rw3h, UBUNTU-CVE-2026-125175.