Impact
In Cilium clusters where Cilium's Layer 7 proxy has been disabled, creating workloads with
policy.cilium.io/proxy-visibility annotations (in Cilium >= v1.13)io.cilium.proxy-visibility annotations (in Cilium <= v1.12)
causes the Cilium agent to segfault on the node to which the workload is assigned.
Existing traffic on the affected node will continue to flow, but the Cilium agent on the node will not able to process changes to workloads running on the node. This will also prevent workloads from being able to start on the affected node. The denial of service will be limited to the node on which the workload is scheduled, however an attacker may be able to schedule workloads on the node of their choosing, which could lead to targeted attacks.
Patches
Pull request with fix
This issue affects:
Cilium <= v1.14.1
Cilium <= v1.13.6
Cilium <= v1.12.13
This issue has been resolved in:
Cilium v1.14.2
Cilium v1.13.7
Cilium v1.12.14
Workarounds
Users can avoid this denial of service attack by enabling the Layer 7 proxy.
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: [email protected] - 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
g-linville Reporter
sayboras Remediation developer
Impact
In Cilium clusters where Cilium's Layer 7 proxy has been disabled, creating workloads with
policy.cilium.io/proxy-visibilityannotations (in Cilium >= v1.13)io.cilium.proxy-visibilityannotations (in Cilium <= v1.12)causes the Cilium agent to segfault on the node to which the workload is assigned.
Existing traffic on the affected node will continue to flow, but the Cilium agent on the node will not able to process changes to workloads running on the node. This will also prevent workloads from being able to start on the affected node. The denial of service will be limited to the node on which the workload is scheduled, however an attacker may be able to schedule workloads on the node of their choosing, which could lead to targeted attacks.
Patches
Pull request with fix
This issue affects:
Cilium <= v1.14.1
Cilium <= v1.13.6
Cilium <= v1.12.13
This issue has been resolved in:
Cilium v1.14.2
Cilium v1.13.7
Cilium v1.12.14
Workarounds
Users can avoid this denial of service attack by enabling the Layer 7 proxy.
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: [email protected] - 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