CVE-2024-45491: Libexpat Project Libexpat

Critical severity, CVSS 9.8. EPSS: 1.1% chance of exploitation in the next 30 days.

An issue was discovered in libexpat before 2.6.3. dtdCopy in xmlparse.c can have an integer overflow for nDefaultAtts on 32-bit platforms (where UINT_MAX equals SIZE_MAX).

Affected products

• Libexpat Project Libexpat: before 2.6.3 (fixed in 2.6.3)

Published 2024-08-30. Last modified 2026-06-17.