Specific Cilium configurations vulnerable to DoS via Kubernetes annotations
Date: 2023-09
Affected: go/github.com/cilium/cilium, go/github.com/cilium/cilium, go/github.com/cilium/cilium
Attack vector: dos
Category: vulnerability-disclosure
Severity: Low
CVE: CVE-2023-41332
CWE: CWE-755
CVSS: 3.5 (CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L)

### 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](https://github.com/cilium/cilium/pull/27597) 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](https://docs.cilium.io/en/latest/community/community/#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](mailto:security@cilium.io) - first,


Mitigations:

Architectural layers (MAESTRO):