Vulnerability 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.
CVSS Score
HIGH
Related Weaknesses (CWE)
References
- https://github.com/strukturag/libheif/commit/a6caa38f7a70d66dc9caec2a7bfe20935b3
- https://github.com/strukturag/libheif/releases/tag/v1.23.0
- https://github.com/strukturag/libheif/security/advisories/GHSA-jvmp-j3cw-84mh
FAQ
What is CVE-2026-50142?
CVE-2026-50142 is a vulnerability with a CVSS score of 7.5 (HIGH). 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 unbound...
How severe is CVE-2026-50142?
CVE-2026-50142 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-50142?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.