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CVE-2026-47251

libheif has an incomplete fix for CVE-2026-3949: integer overflow bypass in vvdec_push_data2

Published: Jul 21, 2026Updated: Jul 27, 2026 Sources: CVE List NVDCWE-125
6.1MEDIUM
NVD MITRE
EPSS Score
0.2%
Top 92.4%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
OpenVAS

Description

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.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:LAC:LPR:NUI:RS:UC:LI:NA:H
Exploitability
AV:LAttack Vector
Local
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:RUser Interaction
Required
Scope
S:UScope
Unchanged
Impact
C:LConfidentiality
Low
I:NIntegrity
None
A:HAvailability
High
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Weaknesses

CWE-125CWE-190

Affected Products

strukturag
oss-projectaka libheif, strukturag/libde265, libde265
libheifLibrary
OSS Libraries / generic-library
struktur
oss-projectaka libheif, libde265 libheif, libde265
libheifLibraryLibrary
OSS Libraries / generic-library

Exploitability

Official Patch Available
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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques
Collection
Initial Access
View detailed technique mapping

References

https://github.com/strukturag/libheif/security/advisories/GHSA-p6q9-fhf2-vj9v
github.com
https://github.com/strukturag/libheif/issues/1712
github.com

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