Cilium is a networking, observability, and security solution with an eBPF-based dataplane. For Cilium users who use Gateway API for Ingress for some services and use LB-IPAM or BGP for LB Service implementation and use network policies to block egress traffic from workloads in a namespace to workloads in other namespaces, egress traffic from workloads covered by such network policies to LoadBalancers configured by Gateway resources will incorrectly be allowed. LoadBalancer resources not deployed via a Gateway API configuration are not affected by this issue. This issue affects: Cilium v1.15 between v1.15.0 and v1.15.14 inclusive, v1.16 between v1.16.0 and v1.16.7 inclusive, and v1.17 between v1.17.0 and v1.17.1 inclusive. This issue is fixed in Cilium v1.15.15, v1.16.8, and v1.17.2. A Clusterwide Cilium Network Policy can be used to work around this issue for users who are unable to upgrade.
Weakness
The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check.
Affected Software
| Name |
Vendor |
Start Version |
End Version |
| Cilium |
Cilium |
1.15.0 (including) |
1.15.15 (excluding) |
| Cilium |
Cilium |
1.16.0 (including) |
1.16.8 (excluding) |
| Cilium |
Cilium |
1.17.0 (including) |
1.17.2 (excluding) |
Potential Mitigations
- Divide the product into anonymous, normal, privileged, and administrative areas. Reduce the attack surface by carefully mapping roles with data and functionality. Use role-based access control (RBAC) [REF-229] to enforce the roles at the appropriate boundaries.
- Note that this approach may not protect against horizontal authorization, i.e., it will not protect a user from attacking others with the same role.
- Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
- For example, consider using authorization frameworks such as the JAAS Authorization Framework [REF-233] and the OWASP ESAPI Access Control feature [REF-45].
- For web applications, make sure that the access control mechanism is enforced correctly at the server side on every page. Users should not be able to access any unauthorized functionality or information by simply requesting direct access to that page.
- One way to do this is to ensure that all pages containing sensitive information are not cached, and that all such pages restrict access to requests that are accompanied by an active and authenticated session token associated with a user who has the required permissions to access that page.
References