CVE-2026-32739

libheif is Vulnerable to Infinite Loop DoS via stts Sample Duration Lookup

MEDIUM
6.5
CVSS Score
Published: May 19, 2026 at 07:10 PM UTC
Updated: July 24, 2026 at 09:23 AM UTC
2 products affected across 2 vendorsLibheifLibheif

Using libheif by strukturag?

Get instant alerts when new vulnerabilities affect libheif - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
MEDIUM6.5
Exploit prediction
EPSS 0.3%
SSVC
PoC

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

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 1.22.0
Affected range stops below 1.22.0, so it looks safe — our inference, not a vendor statement
v < 1.22.0
Affected range stops below 1.22.0, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (2)

x_refsource_CONFIRMExploitVendor Advisory
Source: cverecord
https://github.com/strukturag/libheif/security/advisories/GHSA-j9g7-q9hv-gq8c
x_refsource_MISCRelease Notes
Source: cverecord
https://github.com/strukturag/libheif/releases/tag/v1.22.0

SSVC — Action Prioritization

SSVCPoCNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

6.5MEDIUMGitHub_M
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusANALYZED
CWE
CWE-835

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Free plan, no card