CVSS 4.0
8.7 highCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NCVE-2026-83606
High (8.7). EPSS 0.5% chance of exploitation in the next 30 days. Fixed in @xmldom/xmldom 0.9.11.
xmldom is a pure JavaScript W3C standard-based (XML DOM Level 2 Core) DOMParser and XMLSerializer module. From 0.9.0-beta.9 until 0.9.11, the processing-instruction production in lib/grammar.js lets the greedy S+ separator and lazy Char*? data group repeatedly repartition a long whitespace tail when the required closing ?> is absent. Both parsePI and parseProcessingInstruction apply the expression to the entire remaining source, causing quadratic backtracking during DOMParser.parseFromString() under default options and allowing a small unauthenticated XML input to stall the Node.js event loop. This issue is fixed in @xmldom/xmldom version 0.9.11.
Severity
- EPSS
- 0.5% chance of exploitation in the next 30 days; higher than 44% of CVEs (scores of 2026-10-31)
- CWEs
- CWE-400, CWE-1333
- Published
- Modified
- Record from
- the NVD, synced
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-g53g-w8rj-fmg7 | npm | @xmldom/xmldom | >=0.9.0-beta.9 <0.9.11 | 0.9.11 |
References
- https://github.com/xmldom/xmldom/commit/73df6b8bdbd86f904b9e8c3ab9c49aa54ef2802e
- https://github.com/xmldom/xmldom/pull/1039
- https://github.com/xmldom/xmldom/releases/tag/0.9.11
- https://github.com/xmldom/xmldom/security/advisories/GHSA-g53g-w8rj-fmg7
- https://github.com/xmldom/xmldom/security/advisories/GHSA-g53g-w8rj-fmg7