CVE-2026-22693: harfbuzz_project harfbuzz NULL Pointer Dereference

Vulnerability summary

CVE-2026-22693 is a medium (CVSS 5.3) NULL Pointer Dereference vulnerability in harfbuzz_project harfbuzz. EPSS estimates a 0.45% chance of exploitation in the next 30 days, higher than 37.9% of scored vulnerabilities. 3 public exploits are recorded.

Timeline

1. 10-01-2026
   PublishedVulnerability first disclosed.
2. 12-01-2026
   Last modifiedVulnerability information updated.

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.

• CWE-476NULL Pointer DereferenceThe product dereferences a pointer that it expects to be valid but is NULL.