CVE-2026-44665: CWE-91: XML Injection (aka Blind XPath Injection) in NaturalIntelligence fast-xml-builder
CVE-2026-44665 is an XML Injection vulnerability in the NaturalIntelligence fast-xml-builder library versions prior to 1. 1. 7. The issue occurs when input data contains quotes in attribute values but entity processing is disabled, causing the attribute value to be split into multiple attributes. This allows an attacker to inject unwanted attributes into the generated XML or HTML. The vulnerability has a medium severity with a CVSS score of 6. 1 and was fixed in version 1. 1. 7.
AI Analysis
Technical Summary
The fast-xml-builder library builds XML from JSON input. In versions before 1.1.7, if input attribute values contain quotes and entity processing is not enabled, the library incorrectly parses the attribute value, splitting it into multiple attributes. This parsing flaw enables an attacker to inject additional attributes into the XML or HTML output, leading to XML Injection (CWE-91). The vulnerability is addressed by updating to version 1.1.7 where the parsing logic is corrected.
Potential Impact
An attacker can exploit this vulnerability to inject arbitrary attributes into XML or HTML documents generated by fast-xml-builder, potentially altering the document structure or behavior. The CVSS score of 6.1 indicates a medium impact with partial confidentiality and integrity loss but no availability impact. There are no known exploits in the wild at this time.
Mitigation Recommendations
Upgrade fast-xml-builder to version 1.1.7 or later, where this XML Injection vulnerability is fixed. Since the vendor advisory does not provide additional remediation details, applying the official fix is the recommended action. Patch status is confirmed by the version update; no other mitigations are specified.
CVE-2026-44665: CWE-91: XML Injection (aka Blind XPath Injection) in NaturalIntelligence fast-xml-builder
Description
CVE-2026-44665 is an XML Injection vulnerability in the NaturalIntelligence fast-xml-builder library versions prior to 1. 1. 7. The issue occurs when input data contains quotes in attribute values but entity processing is disabled, causing the attribute value to be split into multiple attributes. This allows an attacker to inject unwanted attributes into the generated XML or HTML. The vulnerability has a medium severity with a CVSS score of 6. 1 and was fixed in version 1. 1. 7.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The fast-xml-builder library builds XML from JSON input. In versions before 1.1.7, if input attribute values contain quotes and entity processing is not enabled, the library incorrectly parses the attribute value, splitting it into multiple attributes. This parsing flaw enables an attacker to inject additional attributes into the XML or HTML output, leading to XML Injection (CWE-91). The vulnerability is addressed by updating to version 1.1.7 where the parsing logic is corrected.
Potential Impact
An attacker can exploit this vulnerability to inject arbitrary attributes into XML or HTML documents generated by fast-xml-builder, potentially altering the document structure or behavior. The CVSS score of 6.1 indicates a medium impact with partial confidentiality and integrity loss but no availability impact. There are no known exploits in the wild at this time.
Mitigation Recommendations
Upgrade fast-xml-builder to version 1.1.7 or later, where this XML Injection vulnerability is fixed. Since the vendor advisory does not provide additional remediation details, applying the official fix is the recommended action. Patch status is confirmed by the version update; no other mitigations are specified.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-05-07T16:20:08.659Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a04a50ccbff5d8610e804b8
Added to database: 5/13/2026, 4:21:32 PM
Last enriched: 5/13/2026, 4:36:42 PM
Last updated: 5/13/2026, 5:27:15 PM
Views: 2
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