CVE-2026-62289

libheif is a HEIF and AVIF file format decoder and encoder. In 1.23.0 and earlier, a crafted HEIF or AVIF file containing a clean aperture box can reduce an image dimension to zero and crash or corrupt tiling results when heif_image_handle_get_image_tiling(handle, 1, &tiling) is called. ImageItem::get_heif_image_tiling() returns already transformed dimensions, and process_image_transformations_on_tiling() applies the clean aperture transformation again. The second application passes zero to Box_clap::left_rounded(0), where image_width minus one underflows and constructs Fraction(0xFFFFFFFF, 2). Debug builds reach an assertion and abort, while release builds can return a corrupt crop and zero-width tiling result. The affected implementation spans libheif/image-items/image_item.cc, libheif/context.cc, and libheif/box.cc. This issue is fixed in version 1.23.1.

These are all security issues fixed in the gdk-pixbuf-loader-libheif-1.23.1-1.1 package on the GA media of openSUSE Tumbleweed.

This update for libheif fixes the following issues:

Update to version 1.23.1 (jsc#PED-16355).

Security issues fixed:

• CVE-2026-62289: integer underflow in Fraction constructor via double clap transform application (bsc#1273079).
• CVE-2026-62291: heap out-of-bounds write in the uncompressed encoder when writing images with mismatched auxiliary alpha dimensions (bsc#1273080).
• CVE-2026-62292: out-of-bounds read in uncompressed unci tile range slicing (bsc#1273081).
• CVE-2026-62377: reachable assertion in HeifContext::get_track() aborts on a valid-but-empty HEIF sequence file (bsc#1273082).
• Heap out-of-bounds write in the uncompressed encoder for RRGGBB images with interleaved bit-depth <= 8 (bsc#1273083).

Changes for libheif:

• Version 1.23.1
  • FFmpeg decoder plugin gains AV1, VVC, JPEG, and JPEG 2000/HTJ2K decoding.
  • SVT-AV1 encoder: new tune=iq and ms-ssim tune parameters.
  • C++ API: added getters/setters for the CLLI and MDCV HDR metadata boxes.
  • Sequence decoder now scales the alpha auxiliary track to the main image size.
  • Fixed pixi box writing for multi-channel images.
  • Corrected the placement of the TAI clock_type field into the top 2 bits.
  • Empty/unset plugin directory is no longer scanned.

This update for libheif fixes the following issues:

Update to version 1.23.1 (jsc#PED-16355).

Security issues fixed:

• CVE-2026-62289: integer underflow in Fraction constructor via double clap transform application (bsc#1273079).
• CVE-2026-62291: heap out-of-bounds write in the uncompressed encoder when writing images with mismatched auxiliary alpha dimensions (bsc#1273080).
• CVE-2026-62292: out-of-bounds read in uncompressed unci tile range slicing (bsc#1273081).
• CVE-2026-62377: reachable assertion in HeifContext::get_track() aborts on a valid-but-empty HEIF sequence file (bsc#1273082).
• Heap out-of-bounds write in the uncompressed encoder for RRGGBB images with interleaved bit-depth <= 8 (bsc#1273083).

Changes for libheif:

• Version 1.23.1
  • FFmpeg decoder plugin gains AV1, VVC, JPEG, and JPEG 2000/HTJ2K decoding.
  • SVT-AV1 encoder: new tune=iq and ms-ssim tune parameters.
  • C++ API: added getters/setters for the CLLI and MDCV HDR metadata boxes.
  • Sequence decoder now scales the alpha auxiliary track to the main image size.
  • Fixed pixi box writing for multi-channel images.
  • Corrected the placement of the TAI clock_type field into the top 2 bits.
  • Empty/unset plugin directory is no longer scanned.

This update for libheif fixes the following issues:

Update to version 1.23.1 (jsc#PED-16355).

Security issues fixed:

• CVE-2026-62289: integer underflow in Fraction constructor via double clap transform application (bsc#1273079).
• CVE-2026-62291: heap out-of-bounds write in the uncompressed encoder when writing images with mismatched auxiliary alpha dimensions (bsc#1273080).
• CVE-2026-62292: out-of-bounds read in uncompressed unci tile range slicing (bsc#1273081).
• CVE-2026-62377: reachable assertion in HeifContext::get_track() aborts on a valid-but-empty HEIF sequence file (bsc#1273082).
• Heap out-of-bounds write in the uncompressed encoder for RRGGBB images with interleaved bit-depth <= 8 (bsc#1273083).

Changes for libheif:

• Version 1.23.1
  • FFmpeg decoder plugin gains AV1, VVC, JPEG, and JPEG 2000/HTJ2K decoding.
  • SVT-AV1 encoder: new tune=iq and ms-ssim tune parameters.
  • C++ API: added getters/setters for the CLLI and MDCV HDR metadata boxes.
  • Sequence decoder now scales the alpha auxiliary track to the main image size.
  • Fixed pixi box writing for multi-channel images.
  • Corrected the placement of the TAI clock_type field into the top 2 bits.
  • Empty/unset plugin directory is no longer scanned.

It was discovered that libheif had an integer underflow in the Fraction constructor when a clap transform was applied twice. An attacker could possibly use this issue to cause libheif to crash, resulting in a denial of service. (CVE-2026-62289)

It was discovered that libheif had an out-of-bounds read in uncompressed tile range slicing. An attacker could possibly use this issue to cause libheif to crash, resulting in a denial of service. This issue only affected Ubuntu 25.10. (CVE-2026-62292)

Feng Ning discovered that libheif incorrectly handled certain image transforms. A remote attacker could possibly use this issue to cause a denial of service. This issue only affected Ubuntu 18.04 LTS, Ubuntu 20.04 LTS, and Ubuntu 22.04 LTS. (CVE-2026-62289)

Ali Firas discovered that libheif incorrectly handled certain images. An attacker could possibly use this issue to cause a denial of service or execute arbitrary code. This issue only affected Ubuntu 24.04 LTS. (CVE-2026-62291)