EUVD-2026-10172

Comprehensive Technical Analysis of EUVD-2026-10172

1. Vulnerability Assessment and Severity Evaluation

Vulnerability Description: The vulnerability affects Parse Server, an open-source backend that can be deployed on any infrastructure running Node.js. Specifically, versions prior to 8.6.10 and 9.5.0-alpha.11 are vulnerable. The issue arises from the Google, Apple, and Facebook authentication adapters, which use JWT (JSON Web Token) verification to validate identity tokens. When the adapter's audience configuration option (clientId for Google/Apple, appIds for Facebook) is not set, JWT verification silently skips audience claim validation. This allows an attacker to use a validly signed JWT issued for a different application to authenticate as any user on the target Parse Server.

Severity Evaluation: The vulnerability has a base score of 9.3 according to CVSS 4.0, indicating a critical severity level. The vector string CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N highlights the following characteristics:

• Attack Vector (AV): Network (N)
• Attack Complexity (AC): Low (L)
• Authentication (AT): None (N)
• Privileges Required (PR): None (N)
• User Interaction (UI): None (N)
• Confidentiality Impact (VC): High (H)
• Integrity Impact (VI): High (H)
• Availability Impact (VA): None (N)
• Scope Change (SC): None (N)
• Secondary Impact (SI): None (N)
• Secondary Availability (SA): None (N)

2. Potential Attack Vectors and Exploitation Methods

Attack Vectors:

• Network-Based Attacks: An attacker can exploit this vulnerability over the network without needing physical access to the system.
• Authentication Bypass: By using a validly signed JWT from a different application, an attacker can authenticate as any user on the target Parse Server.

Exploitation Methods:

• JWT Manipulation: An attacker can craft a JWT with a valid signature but for a different application and use it to authenticate on the target Parse Server.
• Lack of Audience Claim Validation: The absence of audience claim validation allows the attacker to bypass the intended security checks.

3. Affected Systems and Software Versions

Affected Systems:

• Parse Server versions prior to 8.6.10
• Parse Server versions prior to 9.5.0-alpha.11

Software Versions:

• Parse Server < 8.6.10
• Parse Server < 9.5.0-alpha.11

4. Recommended Mitigation Strategies

Immediate Mitigation:

• Upgrade Parse Server: Upgrade to Parse Server version 8.6.10 or 9.5.0-alpha.11 or later.
• Configure Audience Claims: Ensure that the audience configuration option (clientId for Google/Apple, appIds for Facebook) is properly set to enforce JWT validation.

Long-Term Mitigation:

• Regular Security Audits: Conduct regular security audits and vulnerability assessments to identify and mitigate similar issues.
• Monitoring and Logging: Implement robust monitoring and logging to detect and respond to suspicious authentication activities.

5. Impact on European Cybersecurity Landscape

Impact Analysis:

• Widespread Use: Parse Server is widely used in various applications and services across Europe, making this vulnerability a significant risk.
• Data Breaches: The high confidentiality and integrity impact scores indicate that successful exploitation could lead to data breaches, unauthorized access, and potential data manipulation.
• Compliance Risks: Organizations may face compliance issues with regulations such as GDPR if sensitive user data is compromised.

Regulatory Implications:

• GDPR Compliance: Organizations must ensure that they comply with GDPR by protecting user data and reporting any breaches promptly.
• Cybersecurity Directives: Adherence to EU cybersecurity directives and guidelines is crucial to mitigate such vulnerabilities.

6. Technical Details for Security Professionals

Technical Analysis:

• JWT Verification Process: The vulnerability arises from the JWT verification process, where the audience claim is not validated if the configuration option is not set.
• Code Review: Security professionals should review the authentication adapter code to ensure proper validation of JWT claims, including the audience claim.
• Patch Analysis: The patches in versions 8.6.10 and 9.5.0-alpha.11 address the issue by enforcing audience claim validation, even if the configuration option is not set.

Recommendations:

• Security Best Practices: Follow security best practices for JWT implementation, including proper configuration and validation of all claims.
• Incident Response: Develop and maintain an incident response plan to quickly address and mitigate any potential exploitation of this vulnerability.

References:

• GitHub Security Advisory

By addressing this vulnerability promptly and following the recommended mitigation strategies, organizations can significantly reduce the risk of unauthorized access and data breaches, thereby enhancing their overall cybersecurity posture.