{"id":"CVE-2026-125233","state":"PUBLISHED","title":"FFmpeg through 9.0.2 Heap Buffer Overflow via DVB Subtitle Encoder","description":"FFmpeg through 9.0.2 contains a heap buffer overflow vulnerability in dvbsub_encode() in libavcodec/dvbsubenc.c that undercounts each CLUT segment header by two bytes. Attackers can supply a file with many bitmap subtitle rectangles that, when transcoded to the dvbsub encoder, writes past the output buffer and corrupts heap memory.","publishedAt":"2026-11-09T19:11:44.406Z","updatedAt":"2026-11-09T19:11:44.406Z","severity":{"score":8.5,"label":"High","version":"4.0","vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","source":"VulnCheck"},"assigner":"VulnCheck","products":["FFmpeg FFmpeg"],"affected":[{"vendor":"FFmpeg","product":"FFmpeg","packageURL":"pkg:github/ffmpeg/ffmpeg","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThanOrEqual":"9.0.2","versionType":"semver"}],"repo":"https://code.ffmpeg.org/FFmpeg/FFmpeg"}],"references":["https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/24913","https://github.com/FFmpeg/FFmpeg/commit/7f80b2ad83f37a4998d9617495c92b28a7339a90","https://github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/dvbsubenc.c#L363","https://github.com/FFmpeg/FFmpeg","https://www.vulncheck.com/advisories/ffmpeg-through-9.0.2-heap-buffer-overflow-via-dvb-subtitle-encoder"],"weaknesses":["CWE-131"],"ingestedAt":"2026-11-09T19:14:06.399Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/125xxx/CVE-2026-125233.json","commit":"61d6df80db1b12b1399aa01bc455626e606d2471","baselineCommit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-125233","state":"PUBLISHED","datePublished":"2026-11-09T19:11:44.406Z","dateUpdated":"2026-11-09T19:11:44.406Z","assignerShortName":"VulnCheck","assignerOrgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","dateReserved":"2026-11-09T18:15:23.954Z"},"containers":{"cna":{"title":"FFmpeg through 9.0.2 Heap Buffer Overflow via DVB Subtitle Encoder","descriptions":[{"lang":"en","value":"FFmpeg through 9.0.2 contains a heap buffer overflow vulnerability in dvbsub_encode() in libavcodec/dvbsubenc.c that undercounts each CLUT segment header by two bytes. 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