Description
A SAML library not dependent on any frameworks that runs in Node. In version 5.0.1, Node-SAML loads the assertion from the (unsigned) original response document. This is different than the parts that are verified when checking signature. This allows an attacker to modify authentication details within a valid SAML assertion. For example, in one attack it is possible to remove any character from the SAML assertion username. To conduct the attack an attacker would need a validly signed document from the identity provider (IdP). This is fixed in version 5.1.0.
EPSS Score:
0%
Comprehensive Technical Analysis of EUVD-2025-22950
1. Vulnerability Assessment and Severity Evaluation
The vulnerability described in EUVD-2025-22950 pertains to the Node-SAML library, specifically version 5.0.1. The issue arises from the library's handling of SAML assertions, where it loads the assertion from the unsigned original response document rather than verifying the signature of the entire document. This flaw allows an attacker to manipulate authentication details within a valid SAML assertion, potentially leading to unauthorized access or privilege escalation.
Severity Evaluation:
- Base Score: 10.0 (Critical)
- Base Score Version: CVSS 3.1
- Base Score Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N
The high base score indicates a critical vulnerability due to the following factors:
- Attack Vector (AV:N): Network-based attack, meaning the vulnerability can be exploited remotely.
- Attack Complexity (AC:L): Low complexity, indicating that the attack does not require specialized conditions or knowledge.
- Privileges Required (PR:N): No privileges are required to exploit the vulnerability.
- User Interaction (UI:N): No user interaction is required.
- Scope (S:C): The vulnerability affects a different security scope, potentially leading to broader impact.
- Confidentiality (C:H), Integrity (I:H), Availability (A:N): High impact on confidentiality and integrity, with no direct impact on availability.
2. Potential Attack Vectors and Exploitation Methods
Attack Vectors:
- Manipulation of SAML Assertions: An attacker can modify the SAML assertion within a validly signed document from the Identity Provider (IdP). For example, removing characters from the username or altering other authentication details.
- Unauthorized Access: By manipulating the SAML assertion, an attacker can gain unauthorized access to systems or services that rely on SAML for authentication.
Exploitation Methods:
- Intercepting and Modifying SAML Responses: An attacker can intercept the SAML response and modify the assertion before it is processed by the Node-SAML library.
- Crafting Malicious SAML Responses: An attacker with access to a validly signed SAML document can craft a malicious response that includes altered authentication details.
3. Affected Systems and Software Versions
Affected Software:
- Node-SAML Library: Version 5.0.1
Affected Systems:
- Any system or application that uses the Node-SAML library version 5.0.1 for SAML-based authentication.
4. Recommended Mitigation Strategies
Immediate Mitigation:
- Upgrade to Version 5.1.0: The vulnerability is fixed in Node-SAML version 5.1.0. Organizations should upgrade to this version immediately.
- Temporary Workarounds: If upgrading is not immediately possible, consider implementing additional validation checks on SAML assertions to ensure their integrity.
Long-Term Mitigation:
- Regular Security Audits: Conduct regular security audits of authentication mechanisms to identify and mitigate similar vulnerabilities.
- Monitoring and Logging: Implement robust monitoring and logging to detect any suspicious activities related to SAML authentication.
5. Impact on European Cybersecurity Landscape
The vulnerability in the Node-SAML library poses a significant risk to organizations within the European Union that rely on SAML for authentication. Given the critical nature of the vulnerability, it could lead to unauthorized access, data breaches, and potential violations of data protection regulations such as GDPR. The widespread use of Node.js and SAML in enterprise environments amplifies the potential impact, making it crucial for organizations to address this vulnerability promptly.
6. Technical Details for Security Professionals
Vulnerability Details:
- CVE ID: CVE-2025-54419
- Vulnerable Component: Node-SAML library version 5.0.1
- Issue: The library loads the assertion from the unsigned original response document, allowing for manipulation of authentication details.
Exploitation Steps:
- Obtain a Validly Signed SAML Document: The attacker needs a valid SAML document signed by the IdP.
- Modify the SAML Assertion: The attacker modifies the SAML assertion within the document, such as altering the username.
- Submit the Modified Document: The attacker submits the modified SAML document to the service provider (SP) that uses the Node-SAML library.
Detection and Response:
- Signature Verification: Ensure that the entire SAML response, including the assertion, is signed and verified.
- Anomaly Detection: Implement anomaly detection mechanisms to identify unusual patterns in SAML authentication requests.
- Incident Response Plan: Develop and maintain an incident response plan specifically for authentication-related vulnerabilities.
References:
By addressing this vulnerability promptly and implementing robust security measures, organizations can mitigate the risk of unauthorized access and ensure the integrity of their authentication processes.