Description
libheif is a HEIF and AVIF file format decoder and encoder. In versions 1.21.2 and below, a crafted 800-byte HEIF sequence file causes an infinite loop in Box_stts::get_sample_duration(), consuming 100% CPU indefinitely with zero progress, leading to DoS. The loop has no iteration limit or timeout and is triggered during file open (parsing) - before any user interaction or image decoding. The process stays alive (no crash, no error logged), making it invisible to crash-based monitoring. This issue has been fixed in version 1.22.0.
Affected products
struktur: libheif
References3
- github.com/strukturag/libheif/security/advisories/GHSA-j9g7-q9h… ExploitVendor Advisory
- github.com/strukturag/libheif/security/advisories/GHSA-j9g7-q9h… ExploitVendor Advisory
- github.com/strukturag/libheif/releases/tag/v1.22.0 Release Notes
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 25 · as of 14 November 2026
- CWE
- CWE-835
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