Buffer overflow in Strukturag Libheif
CVE-2026-120208
libheif 1.18.0 before 1.23.3 contains a heap-based buffer overflow vulnerability in unc_decoder_mixed_interleave::processTile() that allows attackers to write out of bounds by supplying chroma components with unequal bit depths. Attackers can craft a HEIF file declaring, for example, 16-bit Cb and 8-bit Cr to trigger file-controlled heap writes past the Cr plane, potentially achieving code execution in image-processing pipelines.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- github.com/strukturag/libheif/security/advisories/GHSA-x8r2-mggj-j6wr (vendor-advisory)
- github.com/strukturag/libheif/commit/9d3cd91d7b1c8c68deef6d06057ab956bcb0dfb9 (patch)
- github.com/strukturag/libheif/releases/tag/v1.23.3 (release-notes)
- github.com/strukturag/libheif/blob/v1.23.2/libheif/codecs/uncompressed/unc_deco… (technical-description)
- www.vulncheck.com/advisories/libheif-1.18.0-before-1.23.3-heap-buffer-overflow-… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-120208?
- CVE-2026-120208 is a high-severity vulnerability in Strukturag Libheif, classified under Heap-based Buffer Overflow. CVSS score: 7.5/10. Published 2026-10-31.
- How severe is CVE-2026-120208?
- High severity. CVSS v3 base score is 7.5 out of 10.