CVE-2026-93990 (GCVE-0-2026-93990)
Vulnerability from cvelistv5
Published
2026-09-19 22:58
Modified
2026-09-28 16:11
Severity ?
8.7 (High) - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
CWE
  • CWE-176 - Improper Handling of Unicode Encoding
Summary
Expat before 2.8.5 fails to validate that a high surrogate in UTF-16 input is followed by a low surrogate, allowing malformed UTF-16 sequences to be accepted. Attackers can supply UTF-16 encoded XML containing lone high surrogates that consume the following code unit, causing Expat to pass unpaired surrogates to applications built with XML_UNICODE and to silently replace input characters in other builds.
References
Impacted products
Vendor Product Version
libexpat libexpat Version: 0   ≤
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