CVE-2026-83612

The record

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 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.

Affected packages

Related vulnerabilities

• CVE-2026-86472 fast-uri is a dependency-free RFC 3986 URI parser for Node.js, used by Fastify and ajv. CWE-178
• CVE-2026-87876 Two case-insensitive comparisons on request-derived usernames outside the main… CWE-178
• CVE-2026-84428 fastify versions before 5.12.2 implement the case-insensitive nature of HTTP header names… CWE-178
• CVE-2026-84303 gRPC-Go is the Go language implementation of gRPC. CWE-178
• CVE-2026-73270 Improper Handling of Case Sensitivity vulnerability in Erlang/OTP inets httpd allows a… CWE-178
• CVE-2026-82726 Permissive Regular Expression vulnerability in ash-project ash_phoenix lets a remote… CWE-178
• CVE-2026-78959 Improper handling of case sensitivity in FileSystem in Google Chrome prior to… CWE-178
• CVE-2026-62673 Grav is a file-based Web platform. CWE-178