CVE-2026-83614
xmldom: Quadratic-time parsing via the malformed-input recovery path — `parseElementStartPart` re-scan and `normalize()` adjacent-text merge
Impact
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 packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| npm | @xmldom/xmldom | >= 0.7.0, <= 0.8.14 | 0.8.15 |
| npm | xmldom | >= 0.3.0, <= 0.6.0 | none recorded |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/advisories/GHSA-93r5-fhx6-vmg9
- https://github.com/xmldom/xmldom/security/advisories/GHSA-93r5-fhx6-vmg9
- https://nvd.nist.gov/vuln/detail/CVE-2026-83614
- https://github.com/xmldom/xmldom/pull/1071
- https://github.com/xmldom/xmldom/pull/1072
- https://github.com/xmldom/xmldom/commit/0748720b620555f8c222782dcab575cf0cf403b4
- https://github.com/xmldom/xmldom/commit/f40ccb861eee0acbf5ee4feb9a34932e87b329c9
- https://github.com/xmldom/xmldom/releases/tag/0.8.15
- https://github.com/xmldom/xmldom/releases/tag/0.9.12