EUVD-2025-204596

Comprehensive Technical Analysis of EUVD-2025-204596

1. Vulnerability Assessment and Severity Evaluation

The vulnerability in Ever Gauzy v0.281.9 involves a weak implementation of the HMAC secret key used in JWT (JSON Web Token) authentication. This flaw allows attackers to exploit the JWT token, leading to unauthorized access with administrative permissions. The CVSS (Common Vulnerability Scoring System) base score of 9.3 indicates 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:H/SC:N/SI:N/SA:N highlights the following characteristics:

• Attack Vector (AV): Network (N) - The vulnerability can be exploited remotely over the network.
• Attack Complexity (AC): Low (L) - The attack requires minimal skill or resources.
• Authentication (AT): None (N) - No authentication is required to exploit the vulnerability.
• Privileges Required (PR): None (N) - No special privileges are needed.
• User Interaction (UI): None (N) - No user interaction is required.
• Confidentiality (VC): High (H) - The vulnerability results in a high impact on confidentiality.
• Integrity (VI): High (H) - The vulnerability results in a high impact on integrity.
• Availability (VA): High (H) - The vulnerability results in a high impact on availability.
• Scope (SC): Not Changed (N) - The vulnerability does not change the security scope.
• Scope Integrity (SI): Not Changed (N) - The vulnerability does not change the integrity scope.
• Scope Availability (SA): Not Changed (N) - The vulnerability does not change the availability scope.

2. Potential Attack Vectors and Exploitation Methods

Attackers can exploit this vulnerability by:

• Intercepting JWT Tokens: Capturing JWT tokens through network sniffing or man-in-the-middle attacks.
• Brute-Forcing HMAC Keys: Using computational resources to brute-force the weak HMAC secret key.
• Token Manipulation: Modifying the JWT token to gain unauthorized access, leveraging the weak HMAC implementation.

3. Affected Systems and Software Versions

The vulnerability specifically affects Ever Gauzy version 0.281.9. Other versions may also be affected if they share the same JWT authentication mechanism. Organizations using Ever Gauzy should verify the version in use and apply necessary patches or updates.

4. Recommended Mitigation Strategies

To mitigate this vulnerability, the following steps are recommended:

• Update Software: Immediately update to a patched version of Ever Gauzy that addresses the HMAC secret key weakness.
• Implement Stronger HMAC Keys: Ensure that HMAC keys are sufficiently strong and securely stored.
• Monitor Network Traffic: Use network monitoring tools to detect and respond to unusual JWT token activities.
• Regular Security Audits: Conduct regular security audits to identify and remediate vulnerabilities in authentication mechanisms.
• User Education: Educate users about the risks of weak authentication mechanisms and the importance of strong security practices.

5. Impact on European Cybersecurity Landscape

The vulnerability poses a significant risk to organizations within the European Union, particularly those relying on Ever Gauzy for critical operations. Unauthorized access with administrative permissions can lead to data breaches, financial loss, and reputational damage. Compliance with GDPR (General Data Protection Regulation) may also be compromised, leading to legal and regulatory consequences.

6. Technical Details for Security Professionals

• JWT Structure: JWTs are composed of three parts: Header, Payload, and Signature. The vulnerability lies in the Signature part, which uses a weak HMAC secret key.
• HMAC Implementation: The HMAC (Hash-based Message Authentication Code) is used to verify the integrity and authenticity of the JWT. A weak HMAC key makes it easier for attackers to forge valid tokens.
• Exploit Availability: Exploits for this vulnerability are available in public repositories such as Exploit-DB (https://www.exploit-db.com/exploits/51354).
• References:
  • NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-53951
  • GitHub: https://github.com/ever-co/ever-gauzy
  • VulnCheck: https://www.vulncheck.com/advisories/ever-gauzy-jwt-authentication-weakness-via-hmac-secret

Conclusion

The JWT authentication vulnerability in Ever Gauzy v0.281.9 is critical and requires immediate attention. Organizations should prioritize updating their software and implementing stronger security measures to mitigate the risk. Continuous monitoring and regular security audits are essential to maintain a robust cybersecurity posture in the face of evolving threats.