# CVE-2026-22693: Null Pointer Dereference in SubtableUnicodesCache::create leading to DoS CVE-2026-22693 is fixed in 22 products on 1 platform, first by DEBIAN-CVE-2026-22693, released January 10, 2026. It is not reported as exploited. Patch Radar priority: Routine. - Web page: https://patchblox.com/security/cve/CVE-2026-22693 - Priority: Routine - CVSS: 5.3 (Moderate) - EPSS: 0.0045 - CISA KEV: not listed - Exploited (vendor report): no - Publicly disclosed: no - Published: Jan 10, 2026 - Weakness: NULL Pointer Dereference - Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-22693 ## Description HarfBuzz is a text shaping engine. Prior to version 12.3.0, a null pointer dereference vulnerability exists in the SubtableUnicodesCache::create function located in src/hb-ot-cmap-table.hh. The function fails to check if hb_malloc returns NULL before using placement new to construct an object at the returned pointer address. When hb_malloc fails to allocate memory (which can occur in low-memory conditions or when using custom allocators that simulate allocation failures), it returns NULL. The code then attempts to call the constructor on this null pointer using placement new syntax, resulting in undefined behavior and a Segmentation Fault. This issue has been patched in version 12.3.0. ## Where it's fixed | Platform | Product | Fixed in | Fix | Released | |---|---|---|---|---| | Linux | firefox amzn 2023 | 140.7.0-1.amzn2023.0.3 | [ALAS2023-2026-1435](https://patchblox.com/security/data/fix/linux/alas2023-2026-1435.md) | Feb 16, 2026 | | Linux | firefox-debuginfo amzn 2023 | 140.7.0-1.amzn2023.0.3 | [ALAS2023-2026-1435](https://patchblox.com/security/data/fix/linux/alas2023-2026-1435.md) | Feb 16, 2026 | | Linux | firefox-debugsource amzn 2023 | 140.7.0-1.amzn2023.0.3 | [ALAS2023-2026-1435](https://patchblox.com/security/data/fix/linux/alas2023-2026-1435.md) | Feb 16, 2026 | | Linux | harfbuzz Debian 13.5 (trixie) | 10.2.0-1+deb13u1 | [DEBIAN-CVE-2026-22693](https://patchblox.com/security/data/fix/linux/debian-cve-2026-22693.md) | Jan 10, 2026 | | Linux | harfbuzz Debian 14 | 12.3.0-4 | [DEBIAN-CVE-2026-22693](https://patchblox.com/security/data/fix/linux/debian-cve-2026-22693.md) | Jan 10, 2026 | | Linux | harfbuzz Fedora 43 | 11.5.1-2.fc43 | [FEDORA-2026-B38FE572EF](https://patchblox.com/security/data/fix/linux/fedora-2026-b38fe572ef.md) | Jan 14, 2026 | | Linux | harfbuzz opensuse-leap 15.6 | 8.3.0-150600.3.3.1 | [SUSE-SU-2026:0287-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-0287-1.md) | Jan 23, 2026 | | Linux | harfbuzz opensuse-leap 16.0 | 11.4.5-160000.1.1 | [OPENSUSE-SU-2026:20409-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-20409-1.md) | Mar 20, 2026 | | Linux | harfbuzz sles 15.7 | 8.3.0-150600.3.3.1 | [SUSE-SU-2026:0287-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-0287-1.md) | Jan 23, 2026 | | Linux | harfbuzz sles 16.0 | 11.4.5-160000.1.1 | [SUSE-SU-2026:20922-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-20922-1.md) | Mar 20, 2026 | | Linux | harfbuzz-cairo Fedora 43 | 11.5.1-2.fc43 | [FEDORA-2026-B38FE572EF](https://patchblox.com/security/data/fix/linux/fedora-2026-b38fe572ef.md) | Jan 14, 2026 | | Linux | harfbuzz-cairo-debuginfo Fedora 43 | 11.5.1-2.fc43 | [FEDORA-2026-B38FE572EF](https://patchblox.com/security/data/fix/linux/fedora-2026-b38fe572ef.md) | Jan 14, 2026 | | Linux | harfbuzz-debuginfo Fedora 43 | 11.5.1-2.fc43 | [FEDORA-2026-B38FE572EF](https://patchblox.com/security/data/fix/linux/fedora-2026-b38fe572ef.md) | Jan 14, 2026 | | Linux | harfbuzz-debugsource Fedora 43 | 11.5.1-2.fc43 | [FEDORA-2026-B38FE572EF](https://patchblox.com/security/data/fix/linux/fedora-2026-b38fe572ef.md) | Jan 14, 2026 | | Linux | harfbuzz-devel Fedora 43 | 11.5.1-2.fc43 | [FEDORA-2026-B38FE572EF](https://patchblox.com/security/data/fix/linux/fedora-2026-b38fe572ef.md) | Jan 14, 2026 | | Linux | harfbuzz-devel-debuginfo Fedora 43 | 11.5.1-2.fc43 | [FEDORA-2026-B38FE572EF](https://patchblox.com/security/data/fix/linux/fedora-2026-b38fe572ef.md) | Jan 14, 2026 | | Linux | harfbuzz-icu Fedora 43 | 11.5.1-2.fc43 | [FEDORA-2026-B38FE572EF](https://patchblox.com/security/data/fix/linux/fedora-2026-b38fe572ef.md) | Jan 14, 2026 | | Linux | harfbuzz-icu-debuginfo Fedora 43 | 11.5.1-2.fc43 | [FEDORA-2026-B38FE572EF](https://patchblox.com/security/data/fix/linux/fedora-2026-b38fe572ef.md) | Jan 14, 2026 | | Linux | mingw-harfbuzz Fedora 43 | 11.5.1-2.fc43 | [FEDORA-2026-DC77EB63AE](https://patchblox.com/security/data/fix/linux/fedora-2026-dc77eb63ae.md) | Jan 17, 2026 | | Linux | mingw32-harfbuzz Fedora 43 | 11.5.1-2.fc43 | [FEDORA-2026-DC77EB63AE](https://patchblox.com/security/data/fix/linux/fedora-2026-dc77eb63ae.md) | Jan 17, 2026 | | Linux | mingw32-harfbuzz-debuginfo Fedora 43 | 11.5.1-2.fc43 | [FEDORA-2026-DC77EB63AE](https://patchblox.com/security/data/fix/linux/fedora-2026-dc77eb63ae.md) | Jan 17, 2026 | | Linux | mingw32-harfbuzz-static Fedora 43 | 11.5.1-2.fc43 | [FEDORA-2026-DC77EB63AE](https://patchblox.com/security/data/fix/linux/fedora-2026-dc77eb63ae.md) | Jan 17, 2026 | | Linux | mingw64-harfbuzz Fedora 43 | 11.5.1-2.fc43 | [FEDORA-2026-DC77EB63AE](https://patchblox.com/security/data/fix/linux/fedora-2026-dc77eb63ae.md) | Jan 17, 2026 | | Linux | mingw64-harfbuzz-debuginfo Fedora 43 | 11.5.1-2.fc43 | [FEDORA-2026-DC77EB63AE](https://patchblox.com/security/data/fix/linux/fedora-2026-dc77eb63ae.md) | Jan 17, 2026 | | Linux | mingw64-harfbuzz-static Fedora 43 | 11.5.1-2.fc43 | [FEDORA-2026-DC77EB63AE](https://patchblox.com/security/data/fix/linux/fedora-2026-dc77eb63ae.md) | Jan 17, 2026 | | Linux | perl-HarfBuzz-Shaper Fedora 43 | 0.033-2.fc43 | [FEDORA-2026-2B5249B4B6](https://patchblox.com/security/data/fix/linux/fedora-2026-2b5249b4b6.md) | Jan 20, 2026 | | Linux | perl-HarfBuzz-Shaper-debuginfo Fedora 43 | 0.033-2.fc43 | [FEDORA-2026-2B5249B4B6](https://patchblox.com/security/data/fix/linux/fedora-2026-2b5249b4b6.md) | Jan 20, 2026 | | Linux | perl-HarfBuzz-Shaper-debugsource Fedora 43 | 0.033-2.fc43 | [FEDORA-2026-2B5249B4B6](https://patchblox.com/security/data/fix/linux/fedora-2026-2b5249b4b6.md) | Jan 20, 2026 | --- Data as of 2026-11-08T00:53:09Z UTC. 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