CVE-2025-31492

Remediation / Mitigation Strategy for CVE-2025-31492

Vulnerability Description:

A vulnerability exists in mod_auth_openidc versions prior to 2.4.16.11 that allows for the disclosure of protected content to unauthenticated users. This occurs when using the OIDCProviderAuthRequestMethod POST, a valid user account is present, and no application-level gateway or load balancer protects the server. The server inadvertently appends the protected resource content to the HTTP response even when authentication should have restricted access.

Severity:

High (CVSS Score: 8.2)

Known Exploit:

An attacker can potentially bypass authentication and gain access to sensitive data by crafting requests that meet the vulnerable conditions. Specifically, requesting a protected resource with OIDCProviderAuthRequestMethod POST when no application-level gateway is present will result in unauthorized disclosure of the resource’s content.

Remediation:

  • Upgrade: The primary remediation is to upgrade mod_auth_openidc to version 2.4.16.11 or later. This version contains the necessary patch to prevent the unauthorized disclosure of protected content. # Example using yum (CentOS/RHEL) yum update mod_auth_openidc

    Example using apt (Debian/Ubuntu)

    apt update apt upgrade mod-auth-openidc (Note: The exact commands may vary depending on your Linux distribution and package manager.)

  • Restart Apache: After upgrading mod_auth_openidc, restart the Apache HTTP server to ensure the new version is loaded and active. systemctl restart apache2 # or httpd, depending on your system

Mitigation (if immediate upgrade is not possible):

If an immediate upgrade is not feasible, consider these mitigation strategies:

  • Implement an Application-Level Gateway/Load Balancer: Introducing an application-level gateway or load balancer in front of the Apache server can mitigate the vulnerability. Configure the gateway to enforce proper authentication and authorization before forwarding requests to the backend server.
  • Disable OIDCProviderAuthRequestMethod POST (if possible): If possible, avoid using OIDCProviderAuthRequestMethod POST. Use a different authentication request method. Assess the impact on your application before implementing this mitigation, as it may require significant configuration changes.
  • Web Application Firewall (WAF): Deploy a Web Application Firewall (WAF) and configure it with rules to detect and block requests that attempt to exploit this vulnerability. WAF rules should look for patterns indicative of unauthorized content being returned in the response. This provides a defensive layer but does not eliminate the underlying vulnerability.
  • Monitor and Alert: Implement robust monitoring and alerting to detect any suspicious activity or unauthorized access attempts related to the vulnerability. Log all authentication requests and monitor for unusual response patterns.

Verification:

After applying the remediation or mitigation steps, verify the effectiveness of the solution by:

  • Attempting to reproduce the vulnerability: Try to trigger the vulnerability by sending requests that meet the vulnerable conditions to confirm that the protected content is no longer disclosed.
  • Reviewing Apache logs: Examine the Apache error and access logs for any indications of successful or attempted exploitation.
  • Performing penetration testing: Conduct penetration testing to validate the overall security posture and ensure that the vulnerability has been successfully addressed.

Assigner

Date

  • Published Date: 2025-04-06 20:15:15
  • Updated Date: 2025-04-06 20:15:15

More Details

CVE-2025-31492