Deadlock in libheif - #VU146725
Published: September 2, 2026
Vulnerability identifier: #VU146725
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-833
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to deadlock in ImageItem::decode_image when parsing a crafted file with cyclic auxiliary alpha references. A remote attacker can supply a specially crafted file to cause a denial of service.
The issue is reachable in a default build with default security limits, and a single decode thread can hang permanently.
Affected software
libheif
Remediation
Install security update from vendor's website.
libheif - update to 1.23.3