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 version 0.6.0 and earlier, Document.createProcessingInstruction(target, data) in lib/dom.js accepts an unvalidated target, while the requireWellFormed: true serializer checks only for a colon and the reserved case-insensitive xml name on 0.9.x and performs no target check on 0.8.x. Because serialization emits <?target data?>, a target containing >, ?, whitespace, or another invalid XML-name character can break the processing-instruction boundary and inject XML structure. This issue is fixed in @xmldom/xmldom versions 0.8.15 and 0.9.12; no fixed version is available for xmldom.
References8
- github.com/xmldom/xmldom/commit/1cde3e31a07c41c87cfd368d6946aa4…
- github.com/xmldom/xmldom/commit/3b694872bcb5c7e3cbadba961a4be24…
- github.com/xmldom/xmldom/pull/1071
- github.com/xmldom/xmldom/pull/1072
- github.com/xmldom/xmldom/releases/tag/0.8.15
- github.com/xmldom/xmldom/releases/tag/0.9.12
- github.com/xmldom/xmldom/security/advisories/GHSA-c7q8-3ch8-vqpv
- github.com/xmldom/xmldom/security/advisories/GHSA-c7q8-3ch8-vqpv
Metrics
- CVSS 4.0
-
8.7
HIGH
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 1% percentile: 50 · as of 8 November 2026
- CWE
- CWE-91
Could this be exploited in your environment?
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