HIGHCVSS 8.7
CVE-2026-93990
CVE-2026-93990 updated by NVD
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
Includes data from the National Vulnerability Database (NIST). NVD data is in the public domain; this page is not endorsed by NIST.
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