CVE-2026-75145 FFmpeg Integer Narrowing Conversion OOB Memory Access in AV1 RTP Packetizer
An integer narrowing error in FFmpeg's AV1 RTP packetizer allows out-of-bounds memory access, potentially leading to code execution or crashes.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-75145?
CVE-2026-75145 is a medium-severity vulnerability in FFmpeg, published on 19 Aug 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Official description
FFmpeg before commit b4c199c contains an incorrect integer narrowing conversion in the AV1 RTP packetizer (libavformat/rtpenc_av1.c). The OBU size is cast to long before comparison against the remaining frame size. On targets where long is 32 bits, including 64-bit Windows, sufficiently large OBU size values are sign-flipped by the narrowing cast, producing a negative value that passes the payload size check. This allows an oversized OBU to bypass the safety bound on affected platforms, leading to out-of-bounds memory access when the oversized value is subsequently used as a copy length.
Weakness: CWE-681
Which versions are affected by CVE-2026-75145?
How do I fix CVE-2026-75145?
Apply the vendor's patch.
Is CVE-2026-75145 being exploited?
There is no known exploitation of CVE-2026-75145 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-75145, ECHO-37b9-2184-9e46, GHSA-6fh5-pxvv-ccvw, UBUNTU-CVE-2026-75145.