{"id":"CVE-2026-75145","aliases":[],"title":"FFmpeg Integer Narrowing Conversion OOB Memory Access in AV1 RTP Packetizer","titleSource":"VulnCheck","descriptionSource":"VulnCheck","products":[{"vendor":"FFmpeg","name":"FFmpeg","platforms":[],"versions":[{"version":"0","status":"affected","lessThan":"b4c199c5906ff53368926c2a5839881f41957e7f","versionType":"git"}],"defaultStatus":"unaffected","source":"VulnCheck","url":"https://www.cve.org/CVERecord?id=CVE-2026-75145"}],"remediation":[],"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length.","severity":"medium","score":5.8,"published":"2026-08-19T16:27:33.120Z","modified":"2026-10-27T10:14:32.244Z","withdrawn":false,"knownExploited":false,"affected":[],"references":["https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/24090","https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/b4c199c5906ff53368926c2a5839881f41957e7f","https://www.vulncheck.com/advisories/ffmpeg-integer-narrowing-conversion-oob-memory-access-in-av1-rtp-packetizer"],"sources":[{"name":"CVE","id":"CVE-2026-75145","modified":"2026-10-27T10:14:32.244Z","url":"https://www.cve.org/CVERecord?id=CVE-2026-75145"}],"assessments":[{"source":"VulnCheck","vector":"CVSS:4.0/AV:L/AC:H/AT:N/PR:N/UI:P/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N","score":5.8},{"source":"VulnCheck","vector":"CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:H","score":5.8}],"sourceAffected":[],"kev":{"status":"not-listed","checkedAt":"2026-10-29T00:30:33.731Z"},"coverage":[{"source":"NVD","status":"not-checked"},{"source":"GHSA","status":"not-checked"},{"source":"EUVD","status":"not-checked"},{"source":"EPSS","status":"not-checked"}],"evidence":[]}