A newly discovered vulnerability (CVE-2023-51518) in Apache James prior to versions 3.7.5 and 3.8. allows an attacker to exploit a JMX (Java Management Extension) endpoint that is exposed on the localhost. This vulnerability may enable privilege escalation if an attacker is able to leverage a deserialization gadget as part of an exploit chain. By default, the JMX endpoint is only bound locally, which mitigates the potential threat. However, users should take appropriate measures to safeguard their systems against this vulnerability.

Exploit Details

The vulnerability stems from the way Apache James handles the JMX endpoint, which exposes it to pre-authentication deserialization of untrusted data. The following code snippet demonstrates the issue:

// Vulnerable code snippet in Apache James
public class JamesEndpoint {
    // ...
    private void startJmxEndpoint() {
        try {
            // ...
            JMXServiceURL url = new JMXServiceURL("service:jmx:rmi:///jndi/rmi://localhost:9999/jmxrmi");
            // ...
        } catch (MalformedURLException e) {
            // ...
        }
    }
}

As shown above, the JMX endpoint is hosted on the localhost (127...1) using port 9999, and it is exposed to deserialization of untrusted data by default. An attacker may deploy a deserialization gadget, which is an object that can be serialized into a potentially harmful payload. It is important to note that securing this JMX endpoint is essential to prevent an attacker from injecting malicious deserialization payloads.

Mitigation Recommendations

To counter the CVE-2023-51518 vulnerability, users are urged to upgrade their Apache James installations to either version 3.7.5 or 3.8.. This will eliminate the vulnerability by patching the exposed JMX endpoint. Apache James users should also consider implementing the following security measures:

1. Isolate Apache James from other processes by running it in a Docker container or a dedicated virtual machine. This can prevent an attacker from escalating their privileges by exploiting a deserialization gadget.

2. When feasible, disable the JMX functionality on the Apache James installation. Depending on the requirements of your specific setup, disabling JMX may not always be possible, but doing so can significantly reduce the chances of your system being compromised.

Original References

- Apache James Official Site: https://james.apache.org/
- CVE Details: https://www.cvedetails.com/cve/CVE-2023-51518/
- Vulnerable Apache James Versions: https://james.apache.org/server/security.html#Fixed_in_Apache_James_3.7.5_and_3.8.

Conclusion

CVE-2023-51518 poses a substantial risk to Apache James installations prior to versions 3.7.5 and 3.8.. By following the mitigation steps outlined above and upgrading to a non-vulnerable version of Apache James, users can significantly reduce the risks associated with this vulnerability. Additionally, isolating Apache James from other processes and considering disabling JMX when possible can further fortify your system against deserialization attacks. Always stay informed about the latest vulnerabilities and security patches, and remain vigilant in protecting your systems.

Timeline

Published on: 02/27/2024 09:15:36 UTC
Last modified on: 08/22/2024 21:35:00 UTC