Reliance on undefined behavior in libheif - #VU146737
Published: September 2, 2026
Vulnerability identifier: #VU146737
CSH Severity: Low
CVSS v4: 2 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-758
Exploitation vector: Local 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 reliance on undefined behavior in the Op_to_hdr_planes logic in libheif/color-conversion/hdr_sdr.cc when converting color planes with output bit depths greater than 16. A remote attacker can trigger color conversion with a crafted output bit depth to cause a denial of service.
The issue occurs because a negative shift exponent can be reached during processing, such as when 8-bit input is converted to 20-bit, 24-bit, or 32-bit output.
Affected software
libheif
Remediation
Install security update from vendor's website.
libheif - update to 1.23.3