CVE-2026-47251
mediumpriority · track · 24EPSS 0.002 · 5 %ileEUUSEPSS · scored 2026-10-27
libheif is a HEIF and AVIF file format decoder and encoder. The fix for CVE-2026-3949 (commit `b97c8b5`, PR #1712) introduced an integer overflow in the very security check it added. The check itself can be bypassed, allowing a crafted HEIF file with a VVC track to trigger the same out-of-bounds heap read that CVE-2026-3949 was meant to prevent. This is a separate, currently-unpatched vulnerability. Issue #1712 was closed as fixed without testing the edge case where `size` is near `UINT32_MAX`. Version 1.22.0 patches the issue.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (2)
Products and version ranges known to be affected.
also known as (2)
Other names and identifiers for this entity.
sources
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references (6)
External citations — patches, advisories, analysis.
- https://github.com/strukturag/libheif/issues/1712cnnvd
- https://github.com/strukturag/libheif/security/advisories/GHSA-p6q9-fhf2-vj9vcnnvd
- https://github.com/strukturag/libheif/issues/1712enisa_euvd
- https://github.com/strukturag/libheif/security/advisories/GHSA-p6q9-fhf2-vj9venisa_euvd
- https://github.com/strukturag/libheif/issues/1712Issue Trackingnvd
- https://github.com/strukturag/libheif/security/advisories/GHSA-p6q9-fhf2-vj9vExploitVendor Advisorynvd
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