CVE-2026-47251

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 v3 6.1 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 4.2

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/strukturag/libheif/issues/1712	Issue Tracking
https://github.com/strukturag/libheif/security/advisories/GHSA-p6q9-fhf2-vj9v	Exploit Vendor Advisory
https://github.com/strukturag/libheif/issues/1712	Issue Tracking
https://github.com/strukturag/libheif/security/advisories/GHSA-p6q9-fhf2-vj9v	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:struktur:libheif:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-07-21 22:17

Updated : 2026-07-27 15:19

NVD link : CVE-2026-47251

Mitre link : CVE-2026-47251

CVE.ORG link : CVE-2026-47251

JSON object : View

Products Affected

struktur

libheif

CWE

CWE-125

Out-of-bounds Read

CWE-190

Integer Overflow or Wraparound

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