{"id":"CVE-2026-61784","title":"xhtml-purifier is a Node.js library to take in raw/unknown/untrusted HTML and output cleaned, purified, trusted HTML","summary":"xhtml-purifier is a Node.js library to take in raw/unknown/untrusted HTML and output cleaned, purified, trusted HTML. Versions prior to 0.4.3 do not HTML-entity-encode attribute values when serializing its sanitized output. In attributeS…","severity":"medium","cvss":6.1,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","cwe":["CWE-79","CWE-116"],"vendor":"xhtml-purifier","product":"xhtml-purifier","affected":["xhtml-purifier <= 0.4.1"],"patched":["xhtml-purifier 0.4.3"],"published":"2026-09-24","updated":"2026-09-24","sourceUpdated":"2026-09-24T19:17:15.023","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-61784","references":[{"url":"https://github.com/cstigler/node-xhtml-purifier/commit/21d461ad23e7bc9b3073693d5b51b9b8662044d3","label":"security-advisories@github.com"},{"url":"https://github.com/cstigler/node-xhtml-purifier/security/advisories/GHSA-j8r4-32c5-33rc","label":"security-advisories@github.com"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-61784"},{"url":"https://github.com/cstigler/node-xhtml-purifier/pull/6"},{"url":"https://github.com/cstigler/node-xhtml-purifier/releases/tag/v0.4.3"},{"url":"https://github.com/advisories/GHSA-j8r4-32c5-33rc"}],"tags":["nvd","ghsa","npm","cve.org"],"aliases":["GHSA-j8r4-32c5-33rc"],"ecosystem":"npm","ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-09-24T18:02:51.787487Z"},"ingestedAt":"2026-09-24T17:48:30.403Z","slug":"CVE-2026-61784","body":"## Overview\n\nxhtml-purifier is a Node.js library to take in raw/unknown/untrusted HTML and output cleaned, purified, trusted HTML. Versions prior to 0.4.3 do not HTML-entity-encode attribute values when serializing its sanitized output. In attributeString() (XHTMLPurifier.js, around line 148) the attribute value is concatenated directly into a double-quoted attribute without encoding. As a result, an attacker-controlled value in any allowed attribute (class, style, title, alt, src, href) can include a double-quote character to break out of the attribute and inject an additional attribute, such as a JavaScript event handler (for example onmouseover or onerror). The injected handler survives sanitization and executes when the output is rendered, which is a sanitizer bypass leading to cross-site scripting. The fix in version 0.4.3 HTML-entity-encodes attribute values before serialization.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Package advisory (CVE-2026-61784)\n\nAffected packages:\n\n- `xhtml-purifier <= 0.4.1`\n\nPatched in:\n\n- `xhtml-purifier 0.4.3`\n\nSource: https://github.com/advisories/GHSA-j8r4-32c5-33rc","depth":"sunlit","depthScore":34,"depthScoreParts":{"impact":33.6,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}