CVE-2026-93990
Expat through 2.8.4 Malformed UTF-16 Acceptance via Unchecked Surrogate
Description
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 enabling XML injection attacks.
No summary for this CVE yet.
CVSS Vector Breakdown
Exploitability
AV:NAttack VectorNetwork
AC:LAttack ComplexityLow
PR:NPrivileges RequiredNone
UI:NUser InteractionNone
Scope
S:UScopeUnchanged
Impact
C:NConfidentialityNone
I:HIntegrityHigh
A:NAvailabilityNone
Weaknesses
Affected Products
Exploitability
No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.
References
https://github.com/libexpat/libexpat/pull/1282
github.com
https://github.com/libexpat/libexpat/commit/ff6e1d7e750bbe245178f51a47a965dc8342861a
github.com
https://github.com/libexpat/libexpat
github.com
and 1 more references View all →
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