Instituto Nacional de ciberseguridad. Sección Incibe
Instituto Nacional de Ciberseguridad. Sección INCIBE-CERT

CVE-2026-34401

Gravedad CVSS v3.1:
MEDIA
Tipo:
CWE-611 Restricción incorrecta de referencia a entidad externa XML (XXE)
Fecha de publicación:
31/03/2026
Última modificación:
01/04/2026

Descripción

*** Pendiente de traducción *** XML Notepad is a Windows program that provides a simple intuitive User Interface for browsing and editing XML documents. Prior to version 2.9.0.21, XML Notepad does not disable DTD processing by default which means external entities are resolved automatically. There is a well known attack related to malicious DTD files where an attacker to craft a malicious XML file that loads a DTD that causes XML Notepad to make outbound HTTP/SMB requests, potentially leaking local file contents or capturing the victim's NTLM credentials. This issue has been patched in version 2.9.0.21.