## Critical Vulnerability in fast-xml-parser Allows Comment and CDATA Injection via Unescaped Delimiters
A security vulnerability has been identified in fast-xml-parser, a widely-used XML parsing library, enabling attackers to inject XML comments and CDATA sections through unescaped delimiters. Tracked as CVE-2026-41650 and GHSA-gh4j-gqv2-49f6, the flaw resides specifically in the XMLBuilder component of the parser. The vulnerability affects versions prior to 5.7.0, prompting an urgent dependency update to patch the flaw before it can be exploited in downstream applications.

The issue was automatically closed following a successful update from version 5.5.7 to 5.7.0, managed through automated dependency management tooling. This type of injection vulnerability could allow malicious actors to manipulate XML output structures, potentially bypassing validation checks or injecting arbitrary content into documents processed by applications relying on fast-xml-parser. The risk is particularly acute for systems that serialize untrusted XML data or integrate the parser into web-facing services.

Developers and security teams are urged to verify their dependency trees for any usage of fast-xml-parser versions below 5.7.0. Given the library's prevalence in Node.js and JavaScript ecosystems, the attack surface extends across numerous projects handling XML processing. Immediate patching is recommended, and organizations should audit logs and input sanitization practices to rule out any exploitation attempts during the vulnerable window.
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- **Source**: GitHub Issues
- **Sector**: The Lab
- **Tags**: security-vulnerability, xml-injection, dependency-update, CVE-2026-41650, GHSA
- **Credibility**: unverified
- **Published**: 2026-05-14 09:48:25
- **ID**: 82972
- **URL**: https://whisperx.ai/en/intel/82972