CVE-2026-32738
mediumpriority · track · 26EPSS 0.003 · 23 %ileEURUUSEPSS · scored 2026-10-27
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.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
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weaknesses
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affected products (9)
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also known as (3)
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sources
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references (5)
External citations — patches, advisories, analysis.
- https://access.redhat.com/security/cve/cve-2026-32738cnnvd
- https://github.com/strukturag/libheif/releasesPatchcnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2026-32738cnnvd
- https://github.com/strukturag/libheif/security/advisories/GHSA-7f2h-cmpf-v9wwenisa_euvd
- https://github.com/strukturag/libheif/security/advisories/GHSA-7f2h-cmpf-v9wwExploitVendor Advisorynvd
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