Unencrypted traffic between nodes when using WireGuard and L7 policies

Impact

In Cilium clusters with WireGuard enabled and traffic matching Layer 7 policies:

• Traffic that should be WireGuard-encrypted is sent unencrypted between a node’s Envoy proxy and pods on other nodes.
• Traffic that should be WireGuard-encrypted is sent unencrypted between a node’s DNS proxy and pods on other nodes.

Patches

This issue affects:

• In native routing mode (routingMode=native):
  • Cilium v1.14 versions before v1.14.8
  • Cilium v1.15 versions before v1.15.2
• In tunneling mode (routingMode=tunnel):
  • Cilium v1.14 versions before v1.14.4
  • Cilium v1.14.4 if encryption.wireguard.encapsulate is set to false (default).

This issue has been resolved in:

• In native routing mode (routingMode=native):
  • Cilium v1.14.8
  • Cilium v1.15.2
• In tunneling mode (routingMode=tunnel):
  • Cilium v1.14.4. NOTE encryption.wireguard.encapsulate must be set to true.

Workarounds

There is no workaround to this issue.

Acknowledgements

The Cilium community has worked together with members of Isovalent to prepare these mitigations. Special thanks to @brb, @giorio94, @gandro and @jschwinger233 for their work on triaging and remediating this issue.

For more information

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

If you think you found a related vulnerability, we strongly encourage you to report security vulnerabilities to our private security mailing list at [email protected]. This is a private mailing list where only members of the Cilium internal security team are subscribed to, and your report will be treated as top priority.