Description
libheif is a HEIF and AVIF file format decoder and encoder. In versions 1.21.2 and prior, the inline mask parsing code in `libheif/region.cc` contains an integer overflow. Both `width` and `height` are `unsigned int` (32-bit) values parsed from the HEIF file. Their product can exceed `UINT32_MAX`, wrapping to a small value before the division by 8. This causes an undersized buffer allocation, leading to out-of-bounds memory access when the mask data is later interpreted as a `width x height` bitmap. Version 1.22.0 patches the issue.
Affected products
struktur: libheif
References1
- github.com/strukturag/libheif/security/advisories/GHSA-h4wm-6ww… MitigationVendor Advisory
Metrics
- CVSS 3.1
-
6.1
MEDIUM
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H - EPSS — exploit probability
- 0% percentile: 4 · as of 14 November 2026
- CWE
- CWE-190
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