Vulnerability · Published Sep 1, 2026 · Assigned by GitHub_M
CVE-2026-83616xmldom: Processing Instruction Target Injection Bypasses requireWellFormed
High 8.7
In plain English
A high-severity security flaw in xmldom from xmldom. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 49% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | node-xmldom | no fix listed | DEBIAN-CVE-2026-83616 |
| Debian:13 | node-xmldom | no fix listed | DEBIAN-CVE-2026-83616 |
| Debian:14 | node-xmldom | 0.9.12-1 | DEBIAN-CVE-2026-83616 |
| Ubuntu:22.04:LTS | node-xmldom | no fix listed | UBUNTU-CVE-2026-83616 |
| Ubuntu:24.04:LTS | node-xmldom | no fix listed | UBUNTU-CVE-2026-83616 |
| Ubuntu:26.04:LTS | node-xmldom | no fix listed | UBUNTU-CVE-2026-83616 |
| Ubuntu:26.10 | node-xmldom | no fix listed | UBUNTU-CVE-2026-83616 |
| npm | @xmldom/xmldom | 0.8.15 | GHSA-c7q8-3ch8-vqpv |
| npm | @xmldom/xmldom | 0.9.12 | GHSA-c7q8-3ch8-vqpv |
| npm | xmldom | no fix listed | GHSA-c7q8-3ch8-vqpv |
Affected products (as reported)
Weakness: CWE-91 · Vector: 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
References
- https://github.com/xmldom/xmldom/security/advisories/GHSA-c7q8-3ch8-vqpv x_refsource_CONFIRM
- https://github.com/xmldom/xmldom/pull/1071 x_refsource_MISC
- https://github.com/xmldom/xmldom/pull/1072 x_refsource_MISC
- https://github.com/xmldom/xmldom/commit/1cde3e31a07c41c87cfd368d6946aa477f16b4f9 x_refsource_MISC
- https://github.com/xmldom/xmldom/commit/3b694872bcb5c7e3cbadba961a4be2488750ce5b x_refsource_MISC
- https://github.com/xmldom/xmldom/releases/tag/0.8.15 x_refsource_MISC
- https://github.com/xmldom/xmldom/releases/tag/0.9.12 x_refsource_MISC