Microsoft Security Response Center guidance
Vendor revision: Sep 7, 2026See the Microsoft Security Update Guide for the update that applies to your product.
Vulnerability intelligence
CVE-2026-83619 and is rated High severity with a CVSS score of 8.7. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.
See the Microsoft Security Update Guide for the update that applies to your product.
xmldom is a pure JavaScript W3C standard-based (XML DOM Level 2 Core) DOMParser and XMLSerializer module. From 0.7.0 until 0.8.15, the release-0.8.x parser in lib/sax.js trims captured end-tag names with the unanchored global expression /[ \t\n\r]+$/g.
For an end tag containing a long whitespace run followed by a non-whitespace character, the expression retries from each possible starting position and backtracks quadratically before failing its end anchor. DOMParser.parseFromString() reaches the path under default options, allowing a small unauthenticated XML input to stall the Node.js event loop; the 0.9.x and unscoped npm lines do not contain this expression.
This issue is fixed in @xmldom/xmldom version 0.8.15.
Source: NVD