CVE-2026-93990: fallo de gravedad alta en libexpat
Expat before 2.8.5 Malformed UTF-16 Acceptance via Unchecked Surrogate
Publicada el · Actualizada el
Aviso por correo cuando entre en el KEV, tenga PoC pública o suba de nota.
21Vexday Risk Score
Sin señal de explotación. Ningún artefacto público de explotación conocido hasta ahora.
ssvc Trackcvss 8.7epss 0.4%
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.
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
Productos afectados
libexpat · libexpatCVEs relacionadas — libexpat
En el mismo producto, de las más peligrosas a las menos.
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Referencias
https://blog.hartwork.org/posts/expat-2-8-5-released/https://github.com/libexpat/libexpathttps://github.com/libexpat/libexpat/commit/ff6e1d7e750bbe245178f51a47a965dc8342861ahttps://github.com/libexpat/libexpat/pull/1282https://github.com/libexpat/libexpat/releases/tag/R_2_8_5https://www.vulncheck.com/advisories/expat-through-2.8.4-malformed-utf-16-acceptance-via-unchecked-surrogate