CVE-2023-41332 Denial of service via Kubernetes annotations in specific Cilium configurations
Attackers can cause a denial of service on Cilium nodes by creating workloads with specific annotations when the Layer 7 proxy is disabled.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2023-41332?
CVE-2023-41332 is a low-severity denial of service vulnerability in cilium, published on 26 Sep 2023. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
Cilium is a networking, observability, and security solution with an eBPF-based dataplane. 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) or `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. This issue has been resolved in Cilium versions 1.14.2, 1.13.7, and 1.12.14. Users unable to upgrade can avoid this denial of service attack by enabling the Layer 7 proxy.
Weakness: CWE-755
Which versions are affected by CVE-2023-41332?
14 open source packages ship an affected version, including github.com/cilium/cilium, cilium and cilium-operator. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
github.com/cilium/cilium Go | All versions | 1.12.14, 1.13.7, 1.14.2 |
github.com/cilium/cilium Go | All versions | 1.12.14 |
github.com/cilium/cilium Go | All versions | 1.12.14 |
github.com/cilium/cilium Go | From 1.13.0 | 1.13.7 |
github.com/cilium/cilium Go | From 1.13.0 | 1.13.7 |
github.com/cilium/cilium Go | From 1.14.0 | 1.14.2 |
8 more packages
github.com/cilium/cilium Go | From 1.14.0 | 1.14.2 |
cilium Bitnami | All versions | 1.12.14, 1.13.7, 1.14.2 |
cilium-operator Bitnami | All versions | 1.12.14, 1.13.7, 1.14.2 |
cilium-proxy Bitnami | All versions | 1.12.14, 1.13.7, 1.14.2 |
hubble Bitnami | All versions | 1.12.14, 1.13.7, 1.14.2 |
hubble-relay Bitnami | All versions | 1.12.14, 1.13.7, 1.14.2 |
hubble-ui Bitnami | All versions | 1.12.14, 1.13.7, 1.14.2 |
hubble-ui-backend Bitnami | All versions | 1.12.14, 1.13.7, 1.14.2 |
Products include Cilium Cilium.
How do I fix CVE-2023-41332?
Upgrade github.com/cilium/cilium to a fixed version for your release line: 1.12.14, 1.13.7 or 1.14.2.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2023-41332 being exploited?
There is no known exploitation of CVE-2023-41332 in the wild and no public exploit code.
Other vulnerabilities in cilium
- CVE-2026-49445 Cilium: Sensitive information disclosure and cluster disruption via local Envoy admin socket access
- CVE-2022-29178 Incorrect Default Permissions in Cilium
- CVE-2024-28860 Insecure IPsec transport encryption in Cilium
- CVE-2026-41520 Cillium exposes sensitive information included in the cilium-bugtool debug archive
- CVE-2024-37307 Cilium leaks sensitive information in cilium-bugtool
Sources
Also known as BIT-cilium-2023-41332, BIT-cilium-operator-2023-41332, BIT-cilium-proxy-2023-41332, BIT-hubble-2023-41332, BIT-hubble-relay-2023-41332, BIT-hubble-ui-2023-41332 and 3 more.