EUVD-2026-83618

Expat through 2.8.4 fails to validate low surrogates following high surrogates in UTF-16 input, allowing malformed UTF-16 sequences to be accepted. Attackers can craft UTF-16 encoded XML with lone high surrogates that consume following code units, hiding markup characters from the parser and...

CVE-2026-93990

Expat (libexpat) through 2.8.4 fails to validate low surrogates following high surrogates in UTF-16 input. An attacker can craft UTF-16 encoded XML with lone high surrogates that consume subsequent code units, effectively hiding markup characters from the parser and enabling XML injection . The i...