CVE-2026-75145: ffmpeg

Vulnerability summary

CVE-2026-75145 is a medium (CVSS 5.8) vulnerability in ffmpeg. EPSS estimates a 0.16% chance of exploitation in the next 30 days, higher than 4.5% of scored vulnerabilities.

Timeline

1. 19-08-2026
   PublishedVulnerability first disclosed.
2. 21-08-2026
   Last modifiedVulnerability information updated.

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.

• CWE-681Incorrect Conversion between Numeric TypesWhen converting from one data type to another, such as long to integer, data can be omitted or translated in a way that produces unexpected values. If the resulting values are used in a sensitive context, then dangerous behaviors may occur.