CVE-2023-32187 - Allocation of Resources Without Limits or Throttling Vulnerability in SUSE k3s Allowing DoS Attacks

In this post, we will discuss the details of the CVE-2023-32187 vulnerability, including the affected versions, code snippets, original references, and exploit details. This particular vulnerability is a "Resource Allocation Without Limits or Throttling" issue with SUSE's k3s software that can lead to denial-of-service (DoS) attacks.

Exploit Details

Attackers with access to the K3s server's apiserver/supervisor port (TCP 6443) can exploit this vulnerability to cause a denial-of-service (DoS) attack. By consuming an excessive amount of resources without any limits or throttling in place, attackers can essentially render the k3s system unusable for legitimate users.

Code Snippet

The vulnerable code in SUSE k3s can be found in the affected versions mentioned earlier. Here is a brief code snippet that highlights the issue:

// Example vulnerable code in k3s
func (s *Server) ServeHTTP(w http.ResponseWriter, req *http.Request) {
    // No resource allocation limit or throttling in place
    go s.processRequest(w, req)
}

The above code snippet demonstrates that resource allocations are not limited or throttled, allowing attackers to potentially consume all available resources and cause a DoS attack.

Mitigation

It is strongly recommended to update your k3s version to a patched release to address this vulnerability. Updated versions include:

v1.28.1+k3s1 and later in the v1.28.x series

Patch and update your k3s installations immediately to prevent potential DoS attacks due to this vulnerability.

Original References

1. Official SUSE k3s GitHub Repository: https://github.com/k3s-io/k3s
2. Official SUSE k3s Documentation: https://rancher.com/docs/k3s/latest/en/
3. CVE-2023-32187 Vulnerability Details: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-32187

Conclusion

In summary, the CVE-2023-32187 vulnerability in SUSE k3s is a significant resource allocation issue that could lead to denial-of-service attacks. By understanding the affected versions, code snippets, and original references, users can take the necessary steps to mitigate and patch their k3s systems to ensure the security of their software.

Timeline

Published on: 09/18/2023 13:15:00 UTC
Last modified on: 09/21/2023 15:21:00 UTC