Out-of-bounds Read in Struktur Libheif
CVE-2026-49271
libheif is a HEIF and AVIF file format decoder and encoder. Prior to version 1.22.1, the uncompressed HEIF decoder validates explicit icef compressed-unit offsets using unit_offset + unit_size. Because the addition can wrap, a crafted HEIF file can pass the range check and then construct a vector from iterators outside the compressed item buffer, producing an out-of-bounds heap read and crash. Version 1.22.1 patches the issue.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.004 (26.7th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 27th percentile — 26.7% 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: 0.004 · change: +0.002
Affected products
- Struktur Libheif
- Strukturag Libheif — versions < 1.22.1
Weakness classification (CWE)
References
- github.com/strukturag/libheif/security/advisories/GHSA-r7qj-cg5r-r6vf (Mitigation, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-49271?
- CVE-2026-49271 is a medium-severity vulnerability in Struktur Libheif, classified under Out-of-bounds Read. CVSS score: 6.5/10. Published 2026-06-19.
- How severe is CVE-2026-49271?
- Medium severity. CVSS v3 base score is 6.5 out of 10.