CVE-2026-32738
Severity CVSS v4.0:
Pending analysis
Type:
CWE-125
Out-of-bounds Read
Publication date:
19/05/2026
Last modified:
19/05/2026
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.
Impact
Base Score 3.x
6.50
Severity 3.x
MEDIUM