libheif is a HEIF and AVIF file format decoder and encoder. In versions 1.21.2 and below, a crafted 792-byte HEIF sequence file with samples_per_chunk=0 in the stsc box causes an unsigned integer underflow in the Chunk constructor (m_last_sample = 0 + 0 - 1 = UINT32_MAX), mapping all samples to an empty chunk and resulting in a denial of service. When any sample is accessed, the library reads from index 0 of an empty std::vector, causing a guaranteed SEGV (null-page read). The file parses successfully without producing an error; the crash occurs on the first frame access. This issue has been fixed in version 1.22.0.
History

Wed, 20 May 2026 14:30:00 +0000

Type Values Removed Values Added
CPEs cpe:2.3:a:struktur:libheif:*:*:*:*:*:*:*:*

Wed, 20 May 2026 10:30:00 +0000

Type Values Removed Values Added
First Time appeared Struktur
Struktur libheif
Vendors & Products Struktur
Struktur libheif

Wed, 20 May 2026 00:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-191
References
Metrics threat_severity

None

threat_severity

Moderate


Tue, 19 May 2026 20:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Tue, 19 May 2026 19:15:00 +0000

Type Values Removed Values Added
Description libheif is a HEIF and AVIF file format decoder and encoder. In versions 1.21.2 and below, a crafted 792-byte HEIF sequence file with samples_per_chunk=0 in the stsc box causes an unsigned integer underflow in the Chunk constructor (m_last_sample = 0 + 0 - 1 = UINT32_MAX), mapping all samples to an empty chunk and resulting in a denial of service. When any sample is accessed, the library reads from index 0 of an empty std::vector, causing a guaranteed SEGV (null-page read). The file parses successfully without producing an error; the crash occurs on the first frame access. This issue has been fixed in version 1.22.0.
Title libheif has a Heap OOB Read/SEGV Crash via Zero samples_per_chunk
Weaknesses CWE-125
CWE-476
References
Metrics cvssV3_1

{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-05-19T19:38:59.260Z

Reserved: 2026-03-13T15:02:00.628Z

Link: CVE-2026-32738

cve-icon Vulnrichment

Updated: 2026-05-19T19:33:35.814Z

cve-icon NVD

Status : Analyzed

Published: 2026-05-19T19:16:48.823

Modified: 2026-05-20T14:17:41.080

Link: CVE-2026-32738

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-05-19T19:03:48Z

Links: CVE-2026-32738 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2026-05-20T10:15:15Z