Omni manages Kubernetes on bare metal, virtual machines, or in a cloud. Prior to version 0.48.0, Omni Wireguard SideroLink has the potential to escape. Omni and each Talos machine establish a peer-to-peer (P2P) SideroLink connection using WireGuard to mutually authenticate and authorize access. The WireGuard interface on Omni is configured to ensure that the source IP address of an incoming packet matches the IPv6 address assigned to the Talos peer. However, it performs no validation on the packets destination address. The Talos end of the SideroLink connection cannot be considered a trusted environment. Workloads running on Kubernetes, especially those configured with host networking, could gain direct access to this link. Therefore, a malicious workload could theoretically send arbitrary packets over the SideroLink interface. This issue has been patched in version 0.48.0.
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.
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