CVE-2026-84450
libheif: `clap` + oversized `ispe` aborts on an assert in `Fraction::Fraction` (incomplete fix for CVE-2026-62289)
libheif is a HEIF and AVIF file format decoder and encoder. From 1.19.0 until 1.23.3, a crafted image item containing a clap property and an ispe width or height greater than INT32_MAX + 1 can reach crop calculations through heif_image_handle_get_image_tiling(). Box_clap::left_rounded() or Box_clap::top_rounded() passes the image dimension minus one to Fraction::Fraction(), whose uint32_t constructor uses an assertion as input validation, causing assert-enabled builds to abort. Release builds can instead compute invalid crop geometry, and the tiling API returns dimensions that the normal decode security limits reject. This issue is fixed in version 1.23.3.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- Low
Exploit likelihood
What each source reports
CVE List Score used
4.3
libheif: `clap` + oversized `ispe` aborts on an assert in `Fraction::Fraction` (incomplete fix for CVE-2026-62289)
libheif is a HEIF and AVIF file format decoder and encoder. From 1.19.0 until 1.23.3, a crafted image item containing a clap property and an ispe width or height greater than INT32_MAX + 1 can reach crop calculations through heif_image_handle_get_image_tiling(). Box_clap::left_rounded() or Box_clap::top_rounded() passes the image dimension minus one to Fraction::Fraction(), whose uint32_t constructor uses an assertion as input validation, causing assert-enabled builds to abort. Release builds can instead compute invalid crop geometry, and the tiling API returns dimensions that the normal decode security limits reject. This issue is fixed in version 1.23.3.
- Record
CVE-2026-84450- CVSS 3.1
- 4.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L - Weakness
- CWE-617
- Updated
- 2026-11-02
EUVDEUVD-2026-83028
4.3
libheif is a HEIF and AVIF file format decoder and encoder. From 1.19.0 until 1.23.3, a crafted image item containing a clap property and an ispe width or height greater than INT32_MAX + 1 can reach crop calculations through heif_image_handle_get_image_tiling(). Box_clap::left_rounded() or Box_clap::top_rounded() passes the image dimension minus one to Fraction::Fraction(), whose uint32_t constructor uses an assertion as input validation, causing assert-enabled builds to abort. Release builds can instead compute invalid crop geometry, and the tiling API returns dimensions that the normal decode security limits reject. This issue is fixed in version 1.23.3.
- Record
EUVD-2026-83028- CVSS 3.1
- 4.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L - Updated
- 2026-11-02
NVD
4.3
libheif is a HEIF and AVIF file format decoder and encoder. From 1.19.0 until 1.23.3, a crafted image item containing a clap property and an ispe width or height greater than INT32_MAX + 1 can reach crop calculations through heif_image_handle_get_image_tiling(). Box_clap::left_rounded() or Box_clap::top_rounded() passes the image dimension minus one to Fraction::Fraction(), whose uint32_t constructor uses an assertion as input validation, causing assert-enabled builds to abort. Release builds can instead compute invalid crop geometry, and the tiling API returns dimensions that the normal decode security limits reject. This issue is fixed in version 1.23.3.
- Record
CVE-2026-84450- CVSS 3.1
- 4.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L - Weakness
- CWE-617
- Updated
- 2026-11-02
OSVBELL-CVE-2026-84450
4.3
- Record
BELL-CVE-2026-84450- CVSS 3.1
- 4.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L - Updated
- 2026-11-02
OSV
4.3
libheif: `clap` + oversized `ispe` aborts on an assert in `Fraction::Fraction` (incomplete fix for CVE-2026-62289)
libheif is a HEIF and AVIF file format decoder and encoder. From 1.19.0 until 1.23.3, a crafted image item containing a clap property and an ispe width or height greater than INT32_MAX + 1 can reach crop calculations through heif_image_handle_get_image_tiling(). Box_clap::left_rounded() or Box_clap::top_rounded() passes the image dimension minus one to Fraction::Fraction(), whose uint32_t constructor uses an assertion as input validation, causing assert-enabled builds to abort. Release builds can instead compute invalid crop geometry, and the tiling API returns dimensions that the normal decode security limits reject. This issue is fixed in version 1.23.3.
- Record
CVE-2026-84450- CVSS 3.1
- 4.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L - Weakness
- CWE-617
- Updated
- 2026-11-02
OSVDEBIAN-CVE-2026-84450
4.3
libheif is a HEIF and AVIF file format decoder and encoder. From 1.19.0 until 1.23.3, a crafted image item containing a clap property and an ispe width or height greater than INT32_MAX + 1 can reach crop calculations through heif_image_handle_get_image_tiling(). Box_clap::left_rounded() or Box_clap::top_rounded() passes the image dimension minus one to Fraction::Fraction(), whose uint32_t constructor uses an assertion as input validation, causing assert-enabled builds to abort. Release builds can instead compute invalid crop geometry, and the tiling API returns dimensions that the normal decode security limits reject. This issue is fixed in version 1.23.3.
- Record
DEBIAN-CVE-2026-84450- CVSS 3.1
- 4.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L - Updated
- 2026-11-02
Show 4 moreShow less
OSVopenSUSE-SU-2026:11719-1 No score
gdk-pixbuf-loader-libheif-1.23.4-1.1 on GA media
These are all security issues fixed in the gdk-pixbuf-loader-libheif-1.23.4-1.1 package on the GA media of openSUSE Tumbleweed.
- Record
openSUSE-SU-2026:11719-1- Updated
- 2026-11-02
OSVopenSUSE-SU-2026:21889-1 No score
Security update for libheif
This update for libheif fixes the following issues:
- CVE-2026-84383: Heap buffer overflow in scale_nearest_neighbor() via duplicate alpha planes from nested iden/auxl items (bsc#1279443).
- CVE-2026-84384: brotli/zlib decompression paths lack output-size limits, allowing decompression-bomb OOM/DoS (bsc#1279445).
- CVE-2026-84444: Out-of-bounds write in the unci encoder (bsc#1279448).
- CVE-2026-84446: Sequence decode timing-table initialization allows non-terminating loops and unbounded memory, bypassing max_sequence_frames (bsc#1279447).
- CVE-2026-84447: Derived-image indirect reference chains and tiled offsets bypass decode caching and MemoryHandle limits, causing CPU/memory amplification DoS (bsc#1279446).
- CVE-2026-84448: Heap out-of-bounds read in the inline-mask region API (bsc#1279449).
- CVE-2026-84450: image item with
clapproperty and an ispe declaring a dimension greater thanINT32_MAX + 1can lead to a crash via an abort (bsc#1280002). - CVE-2026-84451: crafted HEIF file advertising a 4096 � 4096 uncompressed tile grid can cause an out-of-bounds read due to an integer overflow (bsc#1280001).
- Heap out-of-bounds write in the uncompressed encoder for RRGGBB images with interleaved bit-depth <= 8 (bsc#1273083).
- Out-of-bounds read and write in derived-item and pixel-plane handling (bsc#1279444).
Changes for libheif:
- Update to version 1.23.4:
- CVE-2026-XXXXX: The max_items security limit was not enforced for the child boxes of iinf, so a file could declare an unbounded number of items.
- CVE-2026-XXXXX: Unbounded recursion in the reference-cycle check crashed the parser on a long chain of derived items, without bound when the item-count limit is disabled.
- CVE-2026-XXXXX: Permanent decoder deadlock through a lock-order inversion in parallel grid tile decoding (enabled by default).
- CVE-2026-XXXXX: Heap out-of-bounds read in the encoder pluginsi for images whose luma and chroma bit depths differ.
- CVE-2026-XXXXX: Unreclaimable memory leak in heif_track_get_next_raw_sequence_sample().
- CVE-2026-XXXXX: Heap out-of-bounds read in the WebCodecs decoder plugin
- includes fixes from 1.23.3:
- CVE-2026-XXXXX: Heap buffer overflow (write) in the uncompressed (unci) mixed-interleave decoder when the two chroma components declare different bit depths.
- CVE-2026-XXXXX: Permanent decoder deadlock through a reference cycle between an image and its alpha auxiliary image.
- CVE-2026-XXXXX: Heap out-of-bounds read in the YCbCr 4:2:0 to 16-bit interleaved RGB conversion when the chroma planes have a lower bit depth than luma
- CVE-2026-XXXXX: Heap buffer overflow in the SVT-AV1 encoder plugin when encoding a high-bit-depth alpha channel, and a double free on its send-picture error path.
- CVE-2026-84451: Incomplete fix: the tile range check of the unci decoder (without icef) could still overflow, allowing an out-of-bounds read
- CVE-2026-XXXXX: Heap out-of-bounds read when converting odd- height 4:2:0 frames of an uncompressed (uncv) image sequence to RGB.
- CVE-2026-XXXXX: Out-of-bounds read in the RGB to YCbCr identity- matrix color conversion when the R, G, and B planes have different bit depths
- CVE-2026-84450: A clap property combined with an oversized ispe reached an assert() in the Fraction arithmetic and aborted the process (incomplete fix). An error is returned instead.
- Fix Several smaller findings
- Fix Undefined behavior (negative shift) in the HDR bit-depth up-conversion for target bit depths above 16. Such conversions are now rejected.
- A number of bug fixes
- Update to version 1.23.2: [jsc#PED-16355]
- CVE-2026-84383: Heap buffer overflow in scale_nearest_neighbor() via duplicate alpha planes from nested iden/auxl items. (boo#CVE-2026-84383)
- Out-of-bounds read and write in derived-item and pixel-plane handling. Through iden and auxl item chains, a crafted file could attach pixel planes whose size differs from the image geometry; crop,…
- Record
openSUSE-SU-2026:21889-1- Updated
- 2026-11-02
OSVSUSE-SU-2026:4276-1 No score
Security update for libheif
This update for libheif fixes the following issues:
- CVE-2026-84383: Heap buffer overflow in scale_nearest_neighbor() via duplicate alpha planes from nested iden/auxl items (bsc#1279443).
- CVE-2026-84384: brotli/zlib decompression paths lack output-size limits, allowing decompression-bomb OOM/DoS (bsc#1279445).
- CVE-2026-84444: Out-of-bounds write in the unci encoder (bsc#1279448).
- CVE-2026-84446: Sequence decode timing-table initialization allows non-terminating loops and unbounded memory, bypassing max_sequence_frames (bsc#1279447).
- CVE-2026-84447: Derived-image indirect reference chains and tiled offsets bypass decode caching and MemoryHandle limits, causing CPU/memory amplification DoS (bsc#1279446).
- CVE-2026-84448: Heap out-of-bounds read in the inline-mask region API (bsc#1279449).
- CVE-2026-84450: image item with
clapproperty and an ispe declaring a dimension greater thanINT32_MAX + 1can lead to a crash via an abort (bsc#1280002). - CVE-2026-84451: crafted HEIF file advertising a 4096 x 4096 uncompressed tile grid can cause an out-of-bounds read due to an integer overflow (bsc#1280001).
- Out-of-bounds read and write in derived-item and pixel-plane handling (bsc#1279444).
Changes for libheif:
- Update to version 1.23.4 (jsc#PED-16355)
- Record
SUSE-SU-2026:4276-1- Updated
- 2026-11-02
OSVUBUNTU-CVE-2026-84450 No score
[Incomplete fix for GHSA-73p7-m7gg-w2jv leaves libheif 1.23.1 vulnerable to an out-of-bounds read]
- Record
UBUNTU-CVE-2026-84450- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
libheifAlpaquita:stream |
1.20.2-r2 up to 1.23.4-r0 | 1.23.4-r0 |
libheifDebian:12 |
All versions, plus listed versions 1.15.1-11.15.1-1+deb12u11.16.2-11.16.2-21.16.2-3 Show 32 moreShow less1.17.0-11.17.1-11.17.4-11.17.6-11.17.6-21.17.6-31.17.6-41.18.1-11.18.1-21.18.2-11.18.2-21.19.1-11.19.1-1~bpo12+11.19.1-1~bpo12+21.19.3-11.19.3-1~bpo12+11.19.5-11.19.7-11.19.7-1~bpo12+11.19.8-11.20.1-11.20.2-11.20.2-21.21.2-11.21.2-21.21.2-31.21.2-41.23.1-11.23.2-11.23.3-11.23.4-11.23.4-1~deb13u1 |
None known |
libheifDebian:13 |
before 1.23.4-1~deb13u1, plus listed versions 1.19.8-11.19.8-1+deb13u11.20.1-11.20.2-11.20.2-2 Show 7 moreShow less1.21.2-11.21.2-21.21.2-31.21.2-41.23.1-11.23.2-11.23.3-1 |
1.23.4-1~deb13u1 |
libheifDebian:14 |
before 1.23.3-1, plus listed versions 1.19.8-11.20.1-11.20.2-11.20.2-21.21.2-1 Show 5 moreShow less1.21.2-21.21.2-31.21.2-41.23.1-11.23.2-1 |
1.23.3-1 |
libheifSUSE:Linux Enterprise Module for Desktop Applications 15 SP7 From an advisory covering 8 CVEs |
before 1.23.4-150700.3.21.1 | 1.23.4-150700.3.21.1 |
libheifSUSE:Linux Enterprise Module for Package Hub 15 SP7 From an advisory covering 8 CVEs |
before 1.23.4-150700.3.21.1 | 1.23.4-150700.3.21.1 |
libheifopenSUSE:Tumbleweed From an advisory covering 8 CVEs |
before 1.23.4-1.1 | 1.23.4-1.1 |
libheifopenSUSE:Leap 16.0 From an advisory covering 8 CVEs |
before 1.23.4-160000.1.1 | 1.23.4-160000.1.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected, facts | ||
| affected | ||
| first indexed | CVE List, EUVD, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-84450 is a medium vulnerability (CVSS 4.3) in Strukturag Libheif, published September 4, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.28%, the 21st percentile. Fixed in libheif 1.23.4-r0.
References
github.com/strukturag/libheif/security/advisories/GHSA-gh5q-69gg-c964
github.com/strukturag/libheif/commit/1c2df9c0e814f89716f3a4d85a444b2dbc63ad69
github.com/strukturag/libheif/releases/tag/v1.23.3
docs.bell-sw.com/security/cves/CVE-2026-84450
github.com/CVEProject/cvelistV5/tree/main/cves/2026/84xxx/CVE-2026-84450.json
nvd.nist.gov/vuln/detail/CVE-2026-84450
Show 23 moreShow less
security-tracker.debian.org/tracker/CVE-2026-84450
suse.com/support/update/announcement/2026/suse-su-20264276-1
bugzilla.suse.com/1279443
bugzilla.suse.com/1279444
bugzilla.suse.com/1279445
bugzilla.suse.com/1279446
bugzilla.suse.com/1279447
bugzilla.suse.com/1279448
bugzilla.suse.com/1279449
bugzilla.suse.com/1280001
bugzilla.suse.com/1280002
suse.com/security/cve/CVE-2026-84383
suse.com/security/cve/CVE-2026-84384
suse.com/security/cve/CVE-2026-84444
suse.com/security/cve/CVE-2026-84446
suse.com/security/cve/CVE-2026-84447
suse.com/security/cve/CVE-2026-84448
suse.com/security/cve/CVE-2026-84450
suse.com/security/cve/CVE-2026-84451
ubuntu.com/security/CVE-2026-84450
cve.org/CVERecord?id=CVE-2026-84450
github.com/strukturag/libheif/security/advisories/GHSA-hh47-fhqr-cj2r
bugzilla.suse.com/1273083
Left out here: the rest of 1 source description. The JSON record has them.