{"id":"CVE-2026-50142","state":"PUBLISHED","title":"libheif: unbounded heap allocation in HEIF sequence parser (stsz fixed-size mode missing bound check)","description":"libheif is a HEIF and AVIF file format decoder and encoder. From 1.19.0 until 1.23.0, a crafted HEIF sequence accepted by heif_context_read_from_memory() with the msf1 sequence brand can cause unbounded heap allocation. In libheif/sequences/seq_boxes.cc, Box_stsz::parse() applies max_sequence_frames only to variable-size samples, so fixed-size mode accepts an attacker-controlled sample_count without a bound. In libheif/sequences/track.cc, Track::load() also adds current_sample_idx and samples_per_chunk in 32-bit arithmetic, allowing the consistency check to be bypassed by wraparound. The resulting values reach the Chunk::Chunk() allocation path, which can consume gigabytes of memory and crash or stall the process through memory exhaustion. This issue is fixed in version 1.23.0.","publishedAt":"2026-08-18T21:18:03.652Z","updatedAt":"2026-08-19T18:51:48.615Z","severity":{"score":7.5,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","source":"GitHub_M"},"assigner":"GitHub_M","products":["strukturag libheif"],"affected":[{"vendor":"strukturag","product":"libheif","versions":[{"version":">= 1.19.0, < 1.23.0","status":"affected"}]}],"references":["https://github.com/strukturag/libheif/security/advisories/GHSA-jvmp-j3cw-84mh","https://github.com/strukturag/libheif/commit/a6caa38f7a70d66dc9caec2a7bfe20935b32c622","https://github.com/strukturag/libheif/releases/tag/v1.23.0"],"weaknesses":["CWE-190","CWE-770"],"ingestedAt":"2026-10-29T20:12:16.098Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/50xxx/CVE-2026-50142.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-50142","state":"PUBLISHED","datePublished":"2026-08-18T21:18:03.652Z","dateUpdated":"2026-08-19T18:51:48.615Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-06-03T18:49:32.275Z"},"containers":{"cna":{"title":"libheif: unbounded heap allocation in HEIF sequence parser (stsz fixed-size mode missing bound check)","descriptions":[{"lang":"en","value":"libheif is a HEIF and AVIF file format decoder and encoder. From 1.19.0 until 1.23.0, a crafted HEIF sequence accepted by heif_context_read_from_memory() with the msf1 sequence brand can cause unbounded heap allocation. In libheif/sequences/seq_boxes.cc, Box_stsz::parse() applies max_sequence_frames only to variable-size samples, so fixed-size mode accepts an attacker-controlled sample_count without a bound. In libheif/sequences/track.cc, Track::load() also adds current_sample_idx and samples_per_chunk in 32-bit arithmetic, allowing the consistency check to be bypassed by wraparound. The resulting values reach the Chunk::Chunk() allocation path, which can consume gigabytes of memory and crash or stall the process through memory exhaustion. This issue is fixed in version 1.23.0."}],"affected":[{"vendor":"strukturag","product":"libheif","versions":[{"version":">= 1.19.0, < 1.23.0","status":"affected"}]}],"references":[{"url":"https://github.com/strukturag/libheif/security/advisories/GHSA-jvmp-j3cw-84mh","name":"https://github.com/strukturag/libheif/security/advisories/GHSA-jvmp-j3cw-84mh","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/strukturag/libheif/commit/a6caa38f7a70d66dc9caec2a7bfe20935b32c622","name":"https://github.com/strukturag/libheif/commit/a6caa38f7a70d66dc9caec2a7bfe20935b32c622","tags":["x_refsource_MISC"]},{"url":"https://github.com/strukturag/libheif/releases/tag/v1.23.0","name":"https://github.com/strukturag/libheif/releases/tag/v1.23.0","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":7.5,"baseSeverity":"HIGH","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-190","lang":"en","description":"CWE-190: Integer Overflow or Wraparound","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-770","lang":"en","description":"CWE-770: Allocation of Resources Without Limits or Throttling","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-08-18T21:18:03.652Z"},"source":{"advisory":"GHSA-jvmp-j3cw-84mh","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-08-19T18:51:41.872528Z","id":"CVE-2026-50142","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-08-19T18:51:48.615Z"}}]}}}