CVE-2026-120208: strukturag libheif

libheif 1.18.0 before 1.23.3 Heap Buffer Overflow via unci Mixed-Interleave Decoder

CVSS 7.7 HighEPSS 0.0037 · 30th percentile

Published by the CVE Program (CNA: VulnCheck) at 31 Oct 2026, 17:25 UTC. agentprime has not analysed this yet, so whether it affects any app is not known. This CVE names a vendor and product rather than a package, so the lockfile check doesn’t match it.

Affected products, as the CNA wrote them
Vendor	Product	Versions
strukturag	libheif	affected 1.18.0 to before 1.23.3 semver Other versions: unaffected

Identifiers

CVE-2026-120208

CNA

VulnCheck

Weakness (CWE)

CWE-122

Not analysed yet

We haven’t published our own analysis of this CVE. If a person reviews it, this page will say what’s affected and what has to be true for it to matter.

Severity and exploitation

Score	Rating	CVSS	Vector	Source
7.7	High	4.0	CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N	CNA (VulnCheck)Used for this record
7.5	High	3.1	CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H	CNA (VulnCheck)

CISA KEV Not listed.
EPSS 0.0037, the 30th percentile, on 7 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

31 Oct 2026, 17:25 UTC Confirmed by the CVE List
31 Oct 2026, 17:36 UTC First seen by agentprime
31 Oct 2026, 18:17 UTC Confirmed by NVD

Sources

References from the CNA

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_decoder_mixed_interleave.cc#L95 technical-description
www.vulncheck.com/advisories/libheif-1.18.0-before-1.23.3-heap-buffer-overflow-via-unci-mixed-interleave-decoder third-party-advisory

Facts on this page come from the CVE List as the CNA published them, with CVSS from the sources named above, CISA KEV and FIRST EPSS. Vendors, products and versions are shown as the CNA wrote them. We don’t reproduce the CVE’s description.