Impact
cilium-cli, when used to configure cluster mesh functionality, can remove the enforcement of user permissions on the etcd store used to mirror local cluster information to remote clusters.
Due to an incorrect mount point specification, the settings specified by the initContainer that configures etcd users and their permissions are overwritten when using cilium-cli to configure a cluster mesh. An attacker who has already gained access to a valid key and certificate for an etcd cluster compromised in this manner could then modify state in that etcd cluster.
Patches
This issue is patched in cilium-cli 0.13.2
All previous versions of cilium-cli are affected. Users who have set up cluster meshes using the Cilium Helm chart are not affected.
Workarounds
Use Cilium's Helm charts to create your cluster instead.
Acknowledgements
The Cilium community has worked together with members of Isovalent to prepare these mitigations. Special thanks to Marco Iorio for investigating and fixing the issue.
For more information
If you have any questions or comments about this advisory, please reach out on Slack.
As usual, if you think you found a related vulnerability, we strongly encourage you to report security vulnerabilities to our private security mailing list: security@cilium.io - first, before disclosing them in any public forums. This is a private mailing list where only members of the Cilium internal security team are subscribed to, and is treated as top priority.
References
giorio94 Finder
Impact
cilium-cli, when used to configure cluster mesh functionality, can remove the enforcement of user permissions on theetcdstore used to mirror local cluster information to remote clusters.Due to an incorrect mount point specification, the settings specified by the
initContainerthat configuresetcdusers and their permissions are overwritten when usingcilium-clito configure a cluster mesh. An attacker who has already gained access to a valid key and certificate for anetcdcluster compromised in this manner could then modify state in thatetcdcluster.Patches
This issue is patched in
cilium-cli0.13.2All previous versions of
cilium-cliare affected. Users who have set up cluster meshes using the Cilium Helm chart are not affected.Workarounds
Use Cilium's Helm charts to create your cluster instead.
Acknowledgements
The Cilium community has worked together with members of Isovalent to prepare these mitigations. Special thanks to Marco Iorio for investigating and fixing the issue.
For more information
If you have any questions or comments about this advisory, please reach out on Slack.
As usual, if you think you found a related vulnerability, we strongly encourage you to report security vulnerabilities to our private security mailing list: security@cilium.io - first, before disclosing them in any public forums. This is a private mailing list where only members of the Cilium internal security team are subscribed to, and is treated as top priority.
References