How to fix CVE-2024-27198 – Step-by-Step Guide
CVE-2024-27198 is a critical authentication bypass vulnerability affecting JetBrains TeamCity. This flaw allows unauthenticated attackers to gain administrative access to the TeamCity server. It poses an immediate and severe risk to affected continuous integration/continuous delivery (CI/CD) environments.
What is JetBrains TeamCity Authentication Bypass?
This vulnerability in JetBrains TeamCity allows an unauthenticated attacker to bypass the authentication mechanism. By exploiting a specific path traversal vulnerability via the web UI, attackers can create new administrator accounts. This grants them full control, enabling arbitrary code execution on the underlying server.
Impact and Risks for your Infrastructure
The impact of CVE-2024-27198 is a complete server takeover. Unauthenticated attackers can create admin accounts, execute arbitrary builds, and access all source code repositories. This leads to the exfiltration of sensitive secrets and credentials stored within TeamCity.
Step-by-Step Mitigation Guide
To mitigate CVE-2024-27198, immediately upgrade your JetBrains TeamCity instance to version 2023.11.4 or newer. Verify the upgrade by checking the TeamCity server version in the administration panel. Ensure all instances are updated to prevent unauthenticated access and code execution.
- 1Update TeamCity to 2023.11.4 or later immediately.
- 2Restrict TeamCity web UI access to trusted IP ranges only.
- 3Audit TeamCity user accounts and remove any unauthorized admin accounts.
- 4Rotate all credentials, tokens, and VCS passwords stored in TeamCity.
- 5Review build logs for signs of exploitation (unauthorized builds, new admin accounts).
- 6Enable TeamCity audit logs and set up alerts for admin account creation.