CVE-2026-72522: Libexpat Project Libexpat

Medium severity, CVSS 6.2. EPSS: 0.2% chance of exploitation in the next 30 days.

libexpat before 2.8.3 has an out-of-bounds read and resultant infinite loop because low surrogates are treated the same as high surrogates during Unicode processing in the *_toUtf16 functions.

Affected products

• Libexpat Project Libexpat: before 2.8.3 (fixed in 2.8.3)

Published 2026-08-10. Last modified 2026-08-31.