CVE-2026-47251
libheif has an incomplete fix for CVE-2026-3949: integer overflow bypass in vvdec_push_data2
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.
INFO
Published Date :
July 21, 2026, 10:17 p.m.
Last Modified :
Oct. 24, 2026, 7:10 p.m.
Remotely Exploit :
No
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | MEDIUM | [email protected] | ||||
| CVSS 4.0 | MEDIUM | [email protected] |
Solution
- Update libheif to version 1.22.0.
- Ensure security checks are tested thoroughly.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-47251.
| URL | 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 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-47251 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-47251
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-47251 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-47251 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Translated by [email protected]
Oct. 24, 2026
Action Type Old Value New Value Added Translation Title: libheif de strukturag, Description: libheif es un decodificador y codificador de formato de archivo HEIF y AVIF. La solución para CVE-2026-3949 (commit ’b97c8b5’, PR #1712) introdujo un desbordamiento de entero en la misma comprobación de seguridad que añadió. La comprobación en sí puede ser eludida, permitiendo que un archivo HEIF manipulado con una pista VVC active la misma lectura de montón fuera de límites que CVE-2026-3949 pretendía evitar. Esta es una vulnerabilidad separada y actualmente sin parchear. El problema #1712 se cerró como solucionado sin probar el caso límite donde ’size’ está cerca de ’UINT32_MAX’. La versión 1.22.0 parchea el problema. -
Initial Analysis by [email protected]
Jul. 27, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H Added CPE Configuration OR *cpe:2.3:a:struktur:libheif:*:*:*:*:*:*:*:* versions up to (excluding) 1.22.0 Added Reference Type GitHub, Inc.: https://github.com/strukturag/libheif/issues/1712 Types: Issue Tracking Added Reference Type GitHub, Inc.: https://github.com/strukturag/libheif/security/advisories/GHSA-p6q9-fhf2-vj9v Types: Exploit, Vendor Advisory Added Reference Type CISA-ADP: https://github.com/strukturag/libheif/issues/1712 Types: Issue Tracking Added Reference Type CISA-ADP: https://github.com/strukturag/libheif/security/advisories/GHSA-p6q9-fhf2-vj9v Types: Exploit, Vendor Advisory -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jul. 22, 2026
Action Type Old Value New Value Added Reference https://github.com/strukturag/libheif/issues/1712 Added Reference https://github.com/strukturag/libheif/security/advisories/GHSA-p6q9-fhf2-vj9v Added SSVC {'id': 'CVE-2026-47251', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-07-22T13:38:27.784638Z'} -
New CVE Received by [email protected]
Jul. 21, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'strukturag', 'product': 'libheif', 'versions': [{'status': 'affected', 'version': '< 1.22.0'}]}] Added 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. Added CVSS V4.0 AV:L/AC:L/AT:N/PR:N/UI:A/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CWE CWE-125 Added CWE CWE-190 Added Reference https://github.com/strukturag/libheif/issues/1712 Added Reference https://github.com/strukturag/libheif/security/advisories/GHSA-p6q9-fhf2-vj9v