{"id":"CVE-2026-83612","title":"xmldom is a pure JavaScript W3C standard-based (XML DOM Level 2 Core) DOMParser and XMLSerializer module","summary":"xmldom is a pure JavaScript W3C standard-based (XML DOM Level 2 Core) DOMParser and XMLSerializer module. From 0.9.0-beta.1 until 0.9.12, HTML-mode parsing through DOMParser.parseFromString() mishandles a mixed-case closing tag for the s…","severity":"high","cwe":["CWE-178","CWE-400"],"vendor":"xmldom","product":"@xmldom/xmldom","affected":["@xmldom/xmldom >= 0.9.0-beta.1, <= 0.9.11"],"patched":["@xmldom/xmldom 0.9.12"],"published":"2026-09-01","updated":"2026-09-08","sourceUpdated":"2026-09-08T21:11:31.703","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-83612","references":[{"url":"https://github.com/xmldom/xmldom/commit/7ced40c06c28d151e996a97045018c3559ae4707","label":"security-advisories@github.com"},{"url":"https://github.com/xmldom/xmldom/pull/1071","label":"security-advisories@github.com"},{"url":"https://github.com/xmldom/xmldom/releases/tag/0.9.12","label":"security-advisories@github.com"},{"url":"https://github.com/xmldom/xmldom/security/advisories/GHSA-6mj3-qw4j-hgrw","label":"security-advisories@github.com"},{"url":"https://github.com/xmldom/xmldom/security/advisories/GHSA-6mj3-qw4j-hgrw","label":"134c704f-9b21-4f2e-91b3-4a467353bcc0"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-83612"},{"url":"https://github.com/advisories/GHSA-6mj3-qw4j-hgrw"}],"tags":["nvd","ghsa","npm"],"aliases":["GHSA-6mj3-qw4j-hgrw"],"ecosystem":"npm","epss":0.00301,"epssPercentile":0.22978,"ingestedAt":"2026-09-08T21:11:12.321Z","slug":"CVE-2026-83612","body":"## Overview\n\nxmldom is a pure JavaScript W3C standard-based (XML DOM Level 2 Core) DOMParser and XMLSerializer module. From 0.9.0-beta.1 until 0.9.12, HTML-mode parsing through DOMParser.parseFromString() mishandles a mixed-case closing tag for the script, style, textarea, or title raw-text elements. parseHtmlSpecialContent, selected by isHTMLRawTextElement or isHTMLEscapableRawTextElement, uses a case-sensitive indexOf() and then calls substring() with a missing-close result of negative one, causing unstable parser progression and quadratic output amplification. A small untrusted text/html document can consequently consume disproportionate CPU and memory when parsed and serialized. This issue is fixed in @xmldom/xmldom version 0.9.12.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Package advisory (CVE-2026-83612)\n\nAffected packages:\n\n- `@xmldom/xmldom >= 0.9.0-beta.1, <= 0.9.11`\n\nPatched in:\n\n- `@xmldom/xmldom 0.9.12`\n\nSource: https://github.com/advisories/GHSA-6mj3-qw4j-hgrw","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}