{"id":"CVE-2026-75145","title":"FFmpeg Integer Narrowing Conversion OOB Memory Access in AV1 RTP Packetizer","summary":"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 …","severity":"medium","cvss":5.8,"cvssVector":"CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:H","cvssSource":"cna","cwe":["CWE-681"],"vendor":"FFmpeg","product":"FFmpeg","affected":["FFmpeg < b4c199c5906ff53368926c2a5839881f41957e7f"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-08-21T19:52:00.435341Z"},"published":"2026-08-19","updated":"2026-10-27","sourceUpdated":"2026-10-27T10:14:32.244Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-75145","references":[{"url":"https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/24090","label":"Pull Request"},{"url":"https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/b4c199c5906ff53368926c2a5839881f41957e7f","label":"Patch Commit"},{"url":"https://www.vulncheck.com/advisories/ffmpeg-integer-narrowing-conversion-oob-memory-access-in-av1-rtp-packetizer"}],"tags":["cve.org"],"epss":0.00158,"epssPercentile":0.04946,"ingestedAt":"2026-10-27T16:11:59.275Z","slug":"CVE-2026-75145","body":"## Overview\n\nFFmpeg 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.\n\n## Affected\n\n- `FFmpeg < b4c199c5906ff53368926c2a5839881f41957e7f`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":32,"depthScoreParts":{"impact":31.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}