CVE-2024-24824

Arbitrary classes can be loaded and instantiated using a HTTP PUT request to the /api/system/cluster_config/ endpoint.

Details

Graylog's cluster config system uses fully qualified class names as config keys. To validate the existence of the requested class before using them, Graylog loads the class using the class loader.

https://github.com/Graylog2/graylog2-server/blob/e458db8bf4f789d4d19f1b37f0263f910c8d036c/graylog2-server/src/main/java/org/graylog2/rest/resources/system/ClusterConfigResource.java#L208-L214

PoC

A request of the following form will output the content of the /etc/passwd file:

curl -u admin:<admin-password> -X PUT http://localhost:9000/api/system/cluster_config/java.io.File \
    -H "Content-Type: application/json" \
    -H "X-Requested-By: poc" \
    -d '"/etc/passwd"'

To perform the request, authorization is required. Only users posessing the clusterconfigentry:create and clusterconfigentry:edit permissions are allowed to do so. These permissions are usually only granted to Admin users.

Credits

Analysis provided by Fabian Yamaguchi - Whirly Labs (Pty) Ltd

If a user with the appropriate permissions performs the request, arbitrary classes with 1-arg String constructors can be instantiated.

This will execute arbitrary code that is run during class instantiation.

In the specific use case of java.io.File, the behaviour of the internal web-server stack will lead to information exposure by including the entire file content in the response to the REST request.

CVE-2024-24824 has a CVSS score of 8.8 (High). The vector is network-reachable, low privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (5.1.11, 5.2.4); upgrading removes the vulnerable code path.

Kodem intelligence

1. What is CVE-2024-24824? CVE-2024-24824 is a high-severity security vulnerability in org.graylog2:graylog2-server (maven), affecting versions >= 2.0.0, < 5.1.11. It is fixed in 5.1.11, 5.2.4.
2. How severe is CVE-2024-24824? CVE-2024-24824 has a CVSS score of 8.8 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of org.graylog2:graylog2-server are affected by CVE-2024-24824? org.graylog2:graylog2-server (maven) versions >= 2.0.0, < 5.1.11 is affected.
4. Is there a fix for CVE-2024-24824? Yes. CVE-2024-24824 is fixed in 5.1.11, 5.2.4. Upgrade to this version or later.
5. Is CVE-2024-24824 exploitable, and should I be worried? Whether CVE-2024-24824 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2024-24824 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2024-24824?
   • Upgrade org.graylog2:graylog2-server to 5.1.11 or later
   • Upgrade org.graylog2:graylog2-server to 5.2.4 or later