Apache Tomcat version older than 7.0.32
Description
Important: Bypass of CSRF prevention filter CVE-2012-4431
Apache Tomcat versions 7.0.0 through 7.0.31 contain a vulnerability in the Cross-Site Request Forgery (CSRF) prevention filter that allows attackers to bypass protection mechanisms. The flaw occurs when a request is made to a protected resource without an existing session identifier, causing the CSRF filter to fail in validating the request's authenticity. This enables attackers to perform unauthorized actions on behalf of authenticated users by exploiting the missing session validation logic.
Affected versions: Apache Tomcat 7.0.0 - 7.0.31
Remediation
Upgrade Apache Tomcat to version 7.0.32 or later to remediate this vulnerability. Follow these steps:
1. Backup your current installation: Create a complete backup of your existing Tomcat configuration, web applications, and data before proceeding.
2. Download the latest version: Obtain Apache Tomcat 7.0.32 or newer from the official Apache Tomcat website (http://tomcat.apache.org/).
3. Test in a non-production environment: Deploy and test the upgraded version with your applications in a staging environment to ensure compatibility.
4. Apply the upgrade: Stop the Tomcat service, replace the installation files with the new version while preserving your configuration files, and restart the service.
5. Verify CSRF protection: Confirm that the CSRF prevention filter is properly configured in your web.xml and functioning correctly after the upgrade.
If immediate upgrading is not possible, review and strengthen session management controls and implement additional CSRF tokens at the application level as a temporary mitigation measure.