What’s Vulnerable › Vulnerabilities

CVE-2026-32739: libheif is Vulnerable to Infinite Loop DoS via stts Sample Duration Lookup

• Severity: medium (CVSS 6.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.3% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2026-05-19 · updated 2026-07-24
• Weakness: CWE-835

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

• strukturag libheif: before 1.22.0 — fixed in 1.22.0

How to fix

Upgrade to a fixed version: strukturag libheif 1.22.0. Check the vendor advisory for mitigations.

References

• https://github.com/strukturag/libheif/releases/tag/v1.22.0
• https://github.com/strukturag/libheif/security/advisories/GHSA-j9g7-q9hv-gq8c
• https://github.com/strukturag/libheif/security/advisories/GHSA-j9g7-q9hv-gq8c

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