{"id":"CVE-2026-84451","published":"2026-09-18T16:17:13.320","lastModified":"2026-09-24T21:18:55.527","description":"libheif is a HEIF and AVIF file format decoder and encoder. From 1.19.0 until 1.23.3, the no-icef full-item branch of unc_decoder::get_compressed_image_data_uncompressed() in libheif/codecs/uncompressed/unc_decoder.cc retains an addition-based range check that can wrap when a crafted uncompressed tile grid produces a large range_start_offset and range_size. The overflow makes the bounds comparison pass and allows heif_image_handle_decode_image_tile() to call memcpy() with an invalid source pointer and a very large length when decoding a valid high-index advertised tile. This incomplete remediation of CVE-2026-62292 can reliably crash tile-processing applications, while whole-image decoding is not claimed to reach the demonstrated path. This issue is fixed in version 1.23.3.","cvssScore":6.5,"cvssSeverity":"MEDIUM","cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","cwes":["CWE-125"],"vendors":[],"products":[],"references":[{"url":"https://github.com/strukturag/libheif/commit/8bfed9a9ed008e4ef28abc736284a90d3cba754f","tags":[]},{"url":"https://github.com/strukturag/libheif/releases/tag/v1.23.3","tags":[]},{"url":"https://github.com/strukturag/libheif/security/advisories/GHSA-hh47-fhqr-cj2r","tags":[]}],"exploitRefs":[{"url":"https://github.com/strukturag/libheif/commit/8bfed9a9ed008e4ef28abc736284a90d3cba754f","tags":[]},{"url":"https://github.com/strukturag/libheif/releases/tag/v1.23.3","tags":[]},{"url":"https://github.com/strukturag/libheif/security/advisories/GHSA-hh47-fhqr-cj2r","tags":[]}],"hasPoc":true,"ai":null}