Out-of-bounds Read in Struktur Libheif
CVE-2026-47254
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.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H.
EPSS exploit prediction
EPSS: 0.002 (5.0th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 5th percentile — 5.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: -0.000
Affected products
- Struktur Libheif
- Strukturag Libheif — versions < 1.22.0
Weakness classification (CWE)
References
- github.com/strukturag/libheif/security/advisories/GHSA-wqjg-4x9g-6cvg (Exploit, Mitigation, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-47254?
- CVE-2026-47254 is a medium-severity vulnerability in Struktur Libheif, classified under Out-of-bounds Read. CVSS score: 6.1/10. Published 2026-07-21.
- How severe is CVE-2026-47254?
- Medium severity. CVSS v3 base score is 6.1 out of 10.