{"id":"CVE-2026-34401","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-34401","generatedAt":"2026-10-28T01:42:23.598Z","title":"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…","description":"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.","published":"2026-03-31T22:16:18.000Z","lastModified":"2026-07-24T21:10:00.000Z","status":"Analyzed","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"3.1","score":6.5,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N"},"cwe":["CWE-611"],"affected":["microsoft/xml notepad"],"epss":{"score":0.00986,"percentile":0.62134,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.99%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"https://github.com/microsoft/XmlNotepad/commit/3665603d61ba10b7827a3724e854748cb780140c","tags":["Patch"],"source":"security-advisories@github.com"},{"url":"https://github.com/microsoft/XmlNotepad/commit/c03ab2311ac6960452eb1ab49098768f851dcc53","tags":["Patch"],"source":"security-advisories@github.com"},{"url":"https://github.com/microsoft/XmlNotepad/releases/tag/2.9.0.21","tags":["Product","Release Notes"],"source":"security-advisories@github.com"},{"url":"https://github.com/microsoft/XmlNotepad/security/advisories/GHSA-5j32-486h-42ch","tags":["Mitigation","Vendor Advisory"],"source":"security-advisories@github.com"},{"url":"https://github.com/microsoft/XmlNotepad/security/advisories/GHSA-5j32-486h-42ch","tags":["Mitigation","Vendor Advisory"],"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-34401","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}