CVE-2025-29775: xml-crypto Auth Bypass Vulnerability

CVE-2025-29775 Overview

xml-crypto is an XML digital signature and encryption library for Node.js. An attacker may be able to exploit a vulnerability in versions prior to 6.0.1, 3.2.1, and 2.1.6 to bypass authentication or authorization mechanisms in systems that rely on xml-crypto for verifying signed XML documents. The vulnerability allows an attacker to modify a valid signed XML message in a way that still passes signature verification checks. For example, it could be used to alter critical identity or access control attributes, enabling an attacker to escalate privileges or impersonate another user. Users of versions 6.0.0 and prior should upgrade to version 6.0.1 to receive a fix. Those who are still using v2.x or v3.x should upgrade to patched versions 2.1.6 or 3.2.1, respectively.

Critical Impact
Potential for privilege escalation or user impersonation without detection during signature verification.

Affected Products

xml-crypto v2.x (prior to 2.1.6)
xml-crypto v3.x (prior to 3.2.1)
xml-crypto v6.0.0

Discovery Timeline

Not Available - Vulnerability discovered by Not Available
Not Available - Responsible disclosure to Not Available
Not Available - CVE CVE-2025-29775 assigned
Not Available - Not Available releases security patch
2025-03-14 - CVE CVE-2025-29775 published to NVD
2025-03-15 - Last updated in NVD database

Technical Details for CVE-2025-29775

Vulnerability Analysis

This vulnerability allows an attacker to alter a signed XML document in a way that maintains its signature verification status, a critical flaw in authentication procedures for XML-based data.

Root Cause

The flaw arises due to improper handling and validation of XML signature elements, allowing unauthorized modifications to go undetected.

Attack Vector

Network

javascript

// Example exploitation code (sanitized)
const xmlCrypto = require('xml-crypto');
const fs = require('fs');
let xmlContent = fs.readFileSync('signed.xml', 'utf8');
xmlContent = xmlContent.replace('OriginalUser', 'MaliciousUser');
xmlCrypto.verifySignature(xmlContent);

Detection Methods for CVE-2025-29775

Indicators of Compromise

Unusual changes in XML signature structures
Anomalous behavior in user authentication logs
Unexplained privilege escalation events

Detection Strategies

Utilize XML schema validation and signature verification library updates to monitor and prevent unauthorized changes to signed XML data.

Monitoring Recommendations

Implement regular audits of authentication logs and setup alerts for any privilege escalations or user impersonation attempts.

How to Mitigate CVE-2025-29775

Immediate Actions Required

Upgrade to xml-crypto version 6.0.1
Verify XML signature handling across applications
Review and improve XML validation processes

Patch Information

Security updates are available at xml-crypto GitHub releases

Workarounds

Users should ensure all XML data is thoroughly validated for unexpected changes, particularly in critical attributes.

bash

# Configuration example
npm update xml-crypto --to=6.0.1