CVE-2024-52529

Workarounds

Users with network policies that match the pattern described above can work around the issue by rewriting any policies that use port ranges to individually specify the ports permitted for traffic.

Acknowledgements

The Cilium community has worked together with members of Isovalent to prepare these mitigations. Special thanks to @jrajahalme for resolving this issue.

For more information

If you have any questions or comments about this advisory, please reach out on Slack.

If you think you have found a vulnerability affecting Cilium, we strongly encourage you to report it to our security mailing list at [email protected]. This is a private mailing list for the Cilium security team, and your report will be treated as top priority.

For users with the following configuration:

• An allow policy that selects a Layer 3 identity and a port range AND
• A Layer 7 allow policy that selects a specific port within the first policy's range

then Layer 7 enforcement would not occur for the traffic selected by the Layer 7 policy.

This issue only affects users who use Cilium's port range functionality, which was introduced in Cilium v1.16.

For reference, an example of a pair of policies that would trigger this issue is:

apiVersion: "cilium.io/v2"
kind: CiliumNetworkPolicy
metadata:
  name: "layer-3-and-4"
spec:
  endpointSelector:
    matchLabels:
      app: service
  ingress:
    - fromCIDR:
      - 192.168.60.0/24
      toPorts:
      - ports:
        - port: "80"
          endPort: 444
          protocol: TCP

and

apiVersion: "cilium.io/v2"
kind: CiliumNetworkPolicy
metadata:
  name: "layer-4-and-7"
spec:
  endpointSelector:
    matchLabels:
      app: service
  ingress:
    toPorts:
    - ports:
      - port: "80"
        protocol: TCP
      rules:
        http:
        - method: "GET"
          path: "/public"

In the above example, requests would be permitted to all HTTP paths on matching endpoints, rather than just GET requests to the /public path as intended by the layer-4-and-7 policy. In patched versions of Cilium, the layer-4-and-7 rule would take precedence over the layer-3-and-4 rule.

The application does not perform an authorization check before performing a sensitive operation. Typical impact: unauthorized access to restricted functionality or data.

CVE-2024-52529 has a CVSS score of 5.8 (Medium). The vector is network-reachable, no 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 (1.16.4); upgrading removes the vulnerable code path.

Kodem intelligence

This issue is patched in https://github.com/cilium/cilium/pull/35150.

This issue affects Cilium v1.16 between v1.16.0 and v1.16.3 inclusive.

This issue is patched in Cilium v1.16.4.

1. What is CVE-2024-52529? CVE-2024-52529 is a medium-severity missing authorization vulnerability in github.com/cilium/cilium (go), affecting versions >= 1.16.0, < 1.16.4. It is fixed in 1.16.4. The application does not perform an authorization check before performing a sensitive operation.
2. How severe is CVE-2024-52529? CVE-2024-52529 has a CVSS score of 5.8 (Medium). 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 github.com/cilium/cilium are affected by CVE-2024-52529? github.com/cilium/cilium (go) versions >= 1.16.0, < 1.16.4 is affected.
4. Is there a fix for CVE-2024-52529? Yes. CVE-2024-52529 is fixed in 1.16.4. Upgrade to this version or later.
5. Is CVE-2024-52529 exploitable, and should I be worried? Whether CVE-2024-52529 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-2024-52529 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-2024-52529? Upgrade github.com/cilium/cilium to 1.16.4 or later.