CVE-2026-41650: CWE-91: XML Injection (aka Blind XPath Injection) in NaturalIntelligence fast-xml-parser
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.
AI Analysis
Technical Summary
The fast-xml-parser library before version 5.7.0 fails to escape certain character sequences in XML comments and CDATA sections when building XML from JavaScript objects. Specifically, the sequences "-->" in comments and "]]>" in CDATA are not escaped, enabling XML injection attacks. This vulnerability is classified as CWE-91 (XML Injection) and can be exploited when untrusted input is processed into XML comments or CDATA, potentially resulting in XSS, SOAP injection, or unauthorized data manipulation. The issue was fixed in version 5.7.0.
Potential Impact
Exploitation of this vulnerability can lead to injection of malicious XML content, which may cause cross-site scripting (XSS), SOAP injection, or manipulation of data processed by applications using the affected library. The CVSS score of 6.1 (medium severity) reflects the network attack vector, low attack complexity, no privileges required, but user interaction needed, and partial impact on confidentiality and integrity without affecting availability.
Mitigation Recommendations
Users should upgrade fast-xml-parser to version 5.7.0 or later, where this vulnerability has been fixed by properly escaping the problematic sequences in XML comments and CDATA sections. No other mitigations are indicated or necessary once the patch is applied.
CVE-2026-41650: CWE-91: XML Injection (aka Blind XPath Injection) in NaturalIntelligence fast-xml-parser
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.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The fast-xml-parser library before version 5.7.0 fails to escape certain character sequences in XML comments and CDATA sections when building XML from JavaScript objects. Specifically, the sequences "-->" in comments and "]]>" in CDATA are not escaped, enabling XML injection attacks. This vulnerability is classified as CWE-91 (XML Injection) and can be exploited when untrusted input is processed into XML comments or CDATA, potentially resulting in XSS, SOAP injection, or unauthorized data manipulation. The issue was fixed in version 5.7.0.
Potential Impact
Exploitation of this vulnerability can lead to injection of malicious XML content, which may cause cross-site scripting (XSS), SOAP injection, or manipulation of data processed by applications using the affected library. The CVSS score of 6.1 (medium severity) reflects the network attack vector, low attack complexity, no privileges required, but user interaction needed, and partial impact on confidentiality and integrity without affecting availability.
Mitigation Recommendations
Users should upgrade fast-xml-parser to version 5.7.0 or later, where this vulnerability has been fixed by properly escaping the problematic sequences in XML comments and CDATA sections. No other mitigations are indicated or necessary once the patch is applied.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-04-21T23:58:43.802Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69fca37ecbff5d8610fd579f
Added to database: 5/7/2026, 2:36:46 PM
Last enriched: 5/7/2026, 2:52:57 PM
Last updated: 5/8/2026, 10:32:44 PM
Views: 9
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