libheif: Out-of-bounds read in uncompressed unci tile range slicing (CVE-2026-62292) | HOL Guard CVE

High · CVSS 8.7CVE-2026-62292

libheif: Out-of-bounds read in uncompressed unci tile range slicing

Answer in brief

CVE-2026-62292 records a High severity (CVSS 8.7) vulnerability in libheif: Out-of-bounds read in uncompressed unci tile range slicing. The current sources do not mark it as known exploited. The current feed maps strukturag/libheif (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Aug 18, 2026Updated Aug 18, 2026Source checked Aug 20, 2026First seen by HOL Aug 18, 2026Material review Aug 18, 2026

Upstream Advisory

Key facts

Risk: High · CVSS 8.7
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Not reported

Why this deserves its current priority

CVSS is 8.7. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps strukturag/libheif (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
strukturag/libheifgeneric	>= 1.19.0, < 1.23.1	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for strukturag/libheif.
Review the reported fix. Monitor this advisory for an available fix and review any installs of the affected package.

Evidence timeline and material changes

Published upstream
Aug 18, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Aug 18, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Aug 18, 2026

Sources and claim methodology

Upstream source description

libheif is a HEIF and AVIF file format decoder and encoder. From 1.19.0 until 1.23.1, a crafted uncompressed HEIF image using generic zlib unci full-item compression can crash an application that decodes an advertised tile with heif_image_handle_decode_image_tile(). In libheif/codecs/uncompressed/unc_decoder.cc, unc_decoder::fetch_tile_data() computes a large tile offset and unc_decoder::get_compressed_image_data_uncompressed() validates it with range_start_offset plus range_size. For the last advertised tile (4095, 4095), the addition can wrap to zero, bypass the bounds check, and pass an invalid source pointer and a one-terabyte length to memcpy. The observed result is an out-of-bounds read and process crash; opening the file alone does not trigger the issue because tile decoding is required. This issue is fixed in version 1.23.1.

Quoted source text, attributed separately from HOL analysis.