Reachable assertion in libheif - #VU146729
Published: September 2, 2026
Vulnerability identifier: #VU146729
CSH Severity: Low
CVSS v4: 4.6 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-617
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 reachable assertion in Fraction::Fraction and Box_clap clap geometry helpers when parsing a crafted AVIF image with a clap property and oversized ispe dimensions. A remote attacker can supply a specially crafted image file to cause a denial of service.
The issue is triggered in assert-enabled builds via the public C API during heif_image_handle_get_image_tiling(), and user interaction is required to open or process the crafted image.
Affected software
libheif
Remediation
Install security update from vendor's website.
libheif - update to 1.23.3