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CVE PROGRAM SOURCE RECORD8.7 High

CVE-2026-83614

xmldom: Quadratic-time parsing via the malformed-input recovery path — `parseElementStartPart` re-scan and `normalize()` adjacent-text merge

Description

xmldom is a pure JavaScript W3C standard-based (XML DOM Level 2 Core) DOMParser and XMLSerializer module. Prior to @xmldom/xmldom versions 0.8.15 and 0.9.12, and in xmldom versions 0.3.0 through 0.6.0, two independent quadratic paths can cause denial of service. In lib/sax.js, parseElementStartPart repeatedly rescans a malformed tag name to the next > during single-character recovery; in lib/dom.js, normalize() repeatedly removes and appends adjacent text nodes, causing quadratic reindexing and string rebuilding. The first path is reachable through default DOMParser.parseFromString() processing, while the second is also reachable through a direct normalize() call on a programmatically constructed DOM, and endDocument invokes that normalization after parsing. This issue is fixed in @xmldom/xmldom versions 0.8.15 and 0.9.12; no fixed version is available for xmldom.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

xmldom xmldom

  • >= 0.3.0, <= 0.6.0affected

@xmldom xmldom

  • >= 0.7.0, < 0.8.15affected
  • >= 0.9.0, < 0.9.12affected

References