Cilium leaks sensitive information in cilium-bugtool

Impact

The output of cilium-bugtool can contain sensitive data when the tool is run (with the --envoy-dump flag set) against Cilium deployments with the Envoy proxy enabled.

Users of the following features are affected:

• TLS inspection
• Ingress with TLS termination
• Gateway API with TLS termination
• Kafka network policies with API key filtering

The sensitive data includes:

• The CA certificate, certificate chain, and private key used by Cilium HTTP Network Policies, and when using Ingress/Gateway API
• The API keys used in Kafka-related network policy

cilium-bugtool is a debugging tool that is typically invoked manually and does not run during the normal operation of a Cilium cluster.

Patches

This issue affects:

• Cilium v1.13 between v1.13.0 and v1.13.16 inclusive
• Cilium v1.14 between v1.14.0 and v1.14.11 inclusive
• Cilium v1.15 between v1.15.0 and v1.15.5 inclusive

This issue has been patched in:

• Cilium v1.15.6
• Cilium v1.14.12
• Cilium v1.13.17

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 @sayboras 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 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.