Description
fast-xml-parser allows users to process XML from JS object without C/C++ based libraries or callbacks. Prior to version 5.7.0, XMLBuilder does not escape the "-->" sequence in comment content or the "]]>" sequence in CDATA sections when building XML from JavaScript objects. This allows XML injection when user-controlled data flows into comments or CDATA elements, leading to XSS, SOAP injection, or data manipulation. This issue has been patched in version 5.7.0.
Affected products
naturalintelligence: fast-xml-parser
References3
- github.com/NaturalIntelligence/fast-xml-parser/security/advisor… ExploitMitigationVendor Advisory
- github.com/NaturalIntelligence/fast-xml-parser/security/advisor… ExploitMitigationVendor Advisory
- github.com/NaturalIntelligence/fast-xml-parser/releases/tag/v5.… ProductRelease Notes
Metrics
- CVSS 3.1
-
6.1
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - EPSS — exploit probability
- 0% percentile: 15 · as of 13 November 2026
- CWE
- CWE-91
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