CVE-2026-41650

MEDIUM

fast-xml-parser XMLBuilder: XML Comment and CDATA Injection via Unescaped Delimiters

Title source: cna

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.

References (2)

Core 2

Core References

X_Refsource_Confirm x_refsource_confirm

https://github.com/NaturalIntelligence/fast-xml-parser/security/advisories/GHSA-gh4j-gqv2-49f6

X_Refsource_Misc x_refsource_misc

https://github.com/NaturalIntelligence/fast-xml-parser/releases/tag/v5.6.0

Scores

CVSS v3 6.1

EPSS 0.0001

EPSS Percentile 1.6%

Attack Vector NETWORK

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

CISA SSVC

Vulnrichment

Exploitation poc

Automatable no

Technical Impact partial

Details

CWE

CWE-91

Status published

Products (3)

naturalintelligence/fast-xml-parser < 5.7.0

NaturalIntelligence/fast-xml-parser < 5.7.0

npm/fast-xml-parser 0 - 5.7.0npm

Published May 07, 2026

Tracked Since May 07, 2026