Medium severity · published May 7, 2026
CVE-2026-41650
fast-xml-parser XMLBuilder: XML Comment and CDATA Injection via Unescaped Delimiters
6.1
CVSS
0.2%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 15% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FA
fast-xml-parser · NaturalIntelligence
< 5.7.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-41650
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-41650
Product
https://github.com/NaturalIntelligence/fast-xml-parser/releases/tag/v5.6.0
Exploit
https://github.com/NaturalIntelligence/fast-xml-parser/security/advisories/GHSA-gh4j-gqv2-49f6
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