{"id":"ALPINE-CVE-2026-50142","details":"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.","modified":"2026-08-27T22:17:57.358422266Z","published":"2026-08-18T22:16:52.633Z","upstream":["CVE-2026-50142"],"references":[{"type":"ADVISORY","url":"https://security.alpinelinux.org/vuln/CVE-2026-50142"}],"affected":[{"package":{"name":"libheif","ecosystem":"Alpine:v3.23","purl":"pkg:apk/alpine/libheif?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.23.0-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/alpine/ALPINE-CVE-2026-50142.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}