{"cve":"CVE-2026-32741","nvd":{"published":"2026-05-19T21:16:42.073","modified":"2026-07-24T09:10:00.153","status":"Deferred","description":"libheif is a HEIF and AVIF file format decoder and encoder. Versions 1.21.2 and below contain a heap buffer overflow in MaskImageCodec::decode_mask_image(). When decoding a HEIF file containing a mask image (mski), the function copies the full iloc extent data into a pixel buffer using memcpy(dst, data.data(), data.size()). The copy length data.size() is determined by the iloc extent in the file (attacker-controlled), while the destination buffer is sized based on the declared image dimensions. Because no upper-bound check exists on the data length, a crafted file whose iloc extent exceeds the pixel buffer allocation overflows the heap. The vulnerable single-memcpy branch is reached when the mskC property specifies bits_per_pixel = 8 and the ispe property declares an even width ≥ 64 (so that stride == width), with no changes to default security limits or external codec plugins required. This issue has been fixed in version 1.22.0.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H","score":7.1},"cwes":["CWE-122","CWE-120"],"references":["https://github.com/strukturag/libheif/releases/tag/v1.22.0","https://github.com/strukturag/libheif/security/advisories/GHSA-j3w5-7whq-p37q","https://access.redhat.com/security/cve/CVE-2026-32741","https://bugzilla.redhat.com/show_bug.cgi?id=2480002","https://github.com/strukturag/libheif/security/advisories/GHSA-j3w5-7whq-p37q"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:35:16.954578616+00:00"},"epss":{"cve":"CVE-2026-32741","score":0.00343,"percentile":0.27904,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}