CVE-2026-47254: Struktur Libheif

Medium severity, CVSS 6.1. EPSS: 0.2% chance of exploitation in the next 30 days.

libheif is a HEIF and AVIF file format decoder and encoder. Prior to version 1.22.0, `Track::init_sample_timing_table()` in `libheif/sequences/track.cc` stores an out-of-bounds chunk index (`m_chunks.size()`) into `m_presentation_timeline` when the number of chunks defined in the `stco` box is less than the number of samples in `stsz`. A subsequent call to `heif_track_get_next_raw_sequence_sample()` reads `m_chunks[chunk_idx]` with that OOB index, causing a heap-buffer-overflow. Version 1.22.0 fixes the issue.

Affected products

• Struktur Libheif: before 1.22.0 (fixed in 1.22.0)

Published 2026-07-21. Last modified 2026-07-27.