CVE-2026-34401 (GCVE-0-2026-34401)
Vulnerability from cvelistv5
Published
2026-03-31 21:05
Modified
2026-04-01 15:53
Severity ?
6.5 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
CWE
  • CWE-611 - Improper Restriction of XML External Entity Reference
Summary
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.
References
Impacted products
Vendor Product Version
microsoft XmlNotepad Version: < 2.9.0.21
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