Cilium vulnerabilities, page 2
39 vulnerabilities
Known vulnerabilities in Cilium products, newest first, with CVSS severity, EPSS, KEV listings and ransomware use, across 4 products.
HighCVE-2024-28860chainguard · hubble-ui +5 moreInsecure IPsec transport encryption in CiliumCilium is a networking, observability, and security solution with an eBPF-based dataplane. Users of IPsec transparent encryption in Cilium may be vulnerable to cryptographic attacks that render the transparent encryption ineffective. In particular, Cilium is vulnerable to chosen plaintext, key recovery, replay attacks by a man-in-the-middle attacker. These attacks are possible due to an ESP sequence number collision when multiple nodes are configured with the same key. Fixed versions of Cilium use unique keys for each IPsec tunnel established between nodes, resolving all of the above attacks. This vulnerability is fixed in 1.13.13, 1.14.9, and 1.15.3.EPSS0.17%HighCVE-2026-41520chainguard · cilium-1.16 +26 moreCillium exposes sensitive information included in the cilium-bugtool debug archiveCilium is a networking, observability, and security solution with an eBPF-based dataplane. Prior to versions 1.17.15, 1.18.9, and 1.19.3, the output of cilium-bugtool can contain sensitive data when the tool is run against Cilium deployments with WireGuard encryption enabled. This issue has been patched in versions 1.17.15, 1.18.9, and 1.19.3.EPSS0.08%MediumCVE-2026-26963cilium +2 moreCilium may not enforce host firewall policies when Native Routing, WireGuard and Node Encryption are enabledCilium is a networking, observability, and security solution with an eBPF-based dataplane. Versions 1.18.0 through 1.18.5 will incorrectly permit traffic from Pods on other nodes when Native Routing, WireGuard and Node Encryption are enabled. This issue has been fixed in version 1.18.6.EPSS0.18%MediumCVE-2026-53935chainguard · cilium-1.16 +25 moreCiliumLocalRedirectPolicy addressMatcher allows cross-namespace service traffic hijacking and can break service translationCilium is a networking, observability, and security solution. Prior to 1.17.16, from 1.18.2 to 1.18.9, and from 1.19.0 to 1.19.3, users with the ability to create CiliumLocalRedirectPolicies can specify arbitrary ClusterIPs via addressMatcher, enabling hijacking traffic to Services in any namespace and bypassing namespace scoping enforced by serviceMatcher; deleting such a policy can also corrupt Cilium internal service state and stop service translation for the affected Service. This issue is fixed in versions 1.17.16, 1.18.10, and 1.19.4.EPSS0.34%HighCVE-2026-56742chainguard · cilium-1.16 +31 moreCilium: Namespaced HTTPRoutes can redirect traffic to other namespacesCilium is a networking, observability, and security solution. Prior to 1.17.17, 1.18.11, and 1.19.5, Cilium clusters using Gateway API allow users with permissions to create or update namespaced HTTPRoutes to mirror HTTP traffic to any Service in any namespace, bypassing the ReferenceGrant authorization mechanism. Gateway API functionality is disabled by default. This issue is fixed in versions 1.17.17, 1.18.11, and 1.19.5.EPSS0.17%MediumCVE-2026-56743chainguard · cilium-1.19-operator-generic +9 moreCilium may unexpectedly allow ingress traffic from the local namespace when a Kubernetes NetworkPolicy is configured with an ipBlock matchCilium is a networking, observability, and security solution. From 1.19.0 to 1.19.4, standard Kubernetes NetworkPolicy specifications using CIDR-based ipBlock rules without pod or namespace selectors erroneously generate a wildcard namespace allow rule when Cilium is configured with a custom clusterName rather than the default any value. The parser incorrectly instantiates a pod selector on selectorless peer definitions, allowing traffic from other workloads in the same namespace as the subject of the policy. This issue is fixed in version 1.19.5.EPSS0.25%MediumCVE-2026-10722chainguard · agentbeat +288 morecilium ebpf LoadCollectionSpec/LoadCollectionSpecFromReader btf.go loadRawSpec integer overflowA vulnerability has been found in cilium ebpf up to 0.21.0. This affects the function loadRawSpec of the file btf/btf.go of the component LoadCollectionSpec/LoadCollectionSpecFromReader. Such manipulation of the argument offset leads to integer overflow. The attack can only be performed from a local environment. The exploit has been disclosed to the public and may be used. The name of the patch is 533dfc82fd228bfadf42ea7180c39de7d9af47fa. A patch should be applied to remediate this issue.EPSS0.18%CriticalCVE-2026-49445chainguard · cilium-1.16 +14 moreCilium: Sensitive information disclosure and cluster disruption via local Envoy admin socket accessCilium is a networking, observability, and security solution. Prior to 1.17.14, 1.18.8, and 1.19.2, when Cilium L7 functionality is enabled, the embedded or standalone Envoy instance creates a world-accessible admin.sock on cluster nodes, allowing a local attacker to access Envoy admin endpoints, expose TLS secrets, disrupt cluster traffic, or terminate Envoy. This issue is fixed in versions 1.17.14, 1.18.8, and 1.19.2.EPSS0.17%MediumCVE-2026-33726chainguard · cilium-1.16 +28 moreCilium L7 proxy may bypass Kubernetes NetworkPolicy for same-node trafficCilium is a networking, observability, and security solution with an eBPF-based dataplane. Prior to versions 1.17.14, 1.18.8, and 1.19.2, Ingress Network Policies are not enforced for traffic from pods to L7 Services (Envoy, GAMMA) with a local backend on the same node, when Per-Endpoint Routing is enabled and BPF Host Routing is disabled. Per-Endpoint Routing is disabled by default, but is automatically enabled in deployments using cloud IPAM, including Cilium ENI on EKS (`eni.enabled`), AlibabaCloud ENI (`alibabacloud.enabled`), Azure IPAM (`azure.enabled`, but not AKS BYOCNI), and some GKE deployments (`gke.enabled`; managed offerings such as GKE Dataplane V2 may use different defaults). It is typically not enabled in tunneled deployments, and chaining deployments are not affected. In practice, Amazon EKS with Cilium ENI mode is likely the most common affected environment. Versions 1.17.14, 1.18.8, and 1.19.2 contain a patch. There is currently no officially verified or comprehensive workaround for this issue. The only option would be to disable per-endpoint routes, but this will likely cause disruptions to ongoing connections, and potential conflicts if running in cloud providers.EPSS0.26%LowCVE-2023-41332chainguard · cilium-1.15 +20 moreDenial of service via Kubernetes annotations in specific Cilium configurationsCilium 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.EPSS0.51%HighCVE-2023-41333chainguard · cilium-1.15 +20 moreBypass of namespace restrictions in CiliumNetworkPolicyCilium is a networking, observability, and security solution with an eBPF-based dataplane. An attacker with the ability to create or modify CiliumNetworkPolicy objects in a particular namespace is able to affect traffic on an entire Cilium cluster, potentially bypassing policy enforcement in other namespaces. By using a crafted `endpointSelector` that uses the `DoesNotExist` operator on the `reserved:init` label, the attacker can create policies that bypass namespace restrictions and affect the entire Cilium cluster. This includes potentially allowing or denying all traffic. This attack requires API server access, as described in the Kubernetes API Server Attacker section of the Cilium Threat Model. This issue has been resolved in Cilium versions 1.14.2, 1.13.7, and 1.12.14. As a workaround an admission webhook can be used to prevent the use of `endpointSelectors` that use the `DoesNotExist` operator on the `reserved:init` label in CiliumNetworkPolicies.EPSS0.48%CriticalCVE-2023-39347chainguard · cilium-1.15 +20 moreCilium NetworkPolicy bypass via pod labelsCilium is a networking, observability, and security solution with an eBPF-based dataplane. An attacker with the ability to update pod labels can cause Cilium to apply incorrect network policies. This issue arises due to the fact that on pod update, Cilium incorrectly uses user-provided pod labels to select the policies which apply to the workload in question. This can affect Cilium network policies that use the namespace, service account or cluster constructs to restrict traffic, Cilium clusterwide network policies that use Cilium namespace labels to select the Pod and Kubernetes network policies. Non-existent construct names can be provided, which bypass all network policies applicable to the construct. For example, providing a pod with a non-existent namespace as the value of the `io.kubernetes.pod.namespace` label results in none of the namespaced CiliumNetworkPolicies applying to the pod in question. This attack requires the attacker to have Kubernetes API Server access, as described in the Cilium Threat Model. This issue has been resolved in: Cilium versions 1.14.2, 1.13.7, and 1.12.14. Users are advised to upgrade. As a workaround an admission webhook can be used to prevent pod label updates to the `k8s:io.kubernetes.pod.namespace` and `io.cilium.k8s.policy.*` keys.EPSS0.57%HighCVE-2023-29002chainguard · hubble-ui-backend +3 moreDebug mode leaks confidential data in CiliumCilium is a networking, observability, and security solution with an eBPF-based dataplane. When run in debug mode, Cilium will log the contents of the `cilium-secrets` namespace. This could include data such as TLS private keys for Ingress and GatewayAPI resources. An attacker with access to debug output from the Cilium containers could use the resulting output to intercept and modify traffic to and from the affected cluster. Output of the sensitive information would occur at Cilium agent restart, when secrets in the namespace are modified, and on creation of Ingress or GatewayAPI resources. This vulnerability is fixed in Cilium releases 1.11.16, 1.12.9, and 1.13.2. Users unable to upgrade should disable debug mode.EPSS0.20%MediumCVE-2023-27593chainguard · cilium-1.15 +18 morecilium-agent container can access the host via `hostPath` mountCilium is a networking, observability, and security solution with an eBPF-based dataplane. Prior to versions 1.11.15, 1.12.8, and 1.13.1, an attacker with access to a Cilium agent pod can write to `/opt/cni/bin` due to a `hostPath` mount of that directory in the agent pod. By replacing the CNI binary with their own malicious binary and waiting for the creation of a new pod on the node, the attacker can gain access to the underlying node.
The issue has been fixed and the fix is available on versions 1.11.15, 1.12.8, and 1.13.1. Some workarounds are available. Kubernetes RBAC should be used to deny users and service accounts `exec` access to Cilium agent pods. In cases where a user requires `exec` access to Cilium agent pods, but should not have access to the underlying node, no workaround is possible.EPSS0.22%CriticalCVE-2023-27595cilium +1 moreCilium eBPF filters may be temporarily removed during agent restartCilium is a networking, observability, and security solution with an eBPF-based dataplane. In version 1.13.0, when Cilium is started, there is a short period when Cilium eBPF programs are not attached to the host. During this period, the host does not implement any of Cilium's featureset. This can cause disruption to newly established connections during this period due to the lack of Load Balancing, or can cause Network Policy bypass due to the lack of Network Policy enforcement during the window. This vulnerability impacts any Cilium-managed endpoints on the node (such as Kubernetes Pods), as well as the host network namespace (including Host Firewall). This vulnerability is fixed in Cilium 1.13.1 or later. Cilium releases 1.12.x, 1.11.x, and earlier are not affected. There are no known workarounds.EPSS0.73%HighCVE-2023-27594chainguard · cilium-1.15 +18 moreCilium vulnerable to potential network policy bypass when routing IPv6 trafficCilium is a networking, observability, and security solution with an eBPF-based dataplane. Prior to versions 1.11.15, 1.12.8, and 1.13.1, under specific conditions, Cilium may misattribute the source IP address of traffic to a cluster, identifying external traffic as coming from the host on which Cilium is running. As a consequence, network policies for that cluster might be bypassed, depending on the specific network policies enabled.
This issue only manifests when Cilium is routing IPv6 traffic and NodePorts are used to route traffic to pods. IPv6 and endpoint routes are both disabled by default.
The problem has been fixed and is available on versions 1.11.15, 1.12.8, and 1.13.1. As a workaround, disable IPv6 routing.EPSS0.55%MediumCVE-2023-28114cilium · cilium-cli +1 more`cilium-cli` disables etcd authorization for clustermesh clusters`cilium-cli` is the command line interface to install, manage, and troubleshoot Kubernetes clusters running Cilium. Prior to version 0.13.2,`cilium-cli`, when used to configure cluster mesh functionality, can remove the enforcement of user permissions on the `etcd` store used to mirror local cluster information to remote clusters. Users who have set up cluster meshes using the Cilium Helm chart are not affected by this issue.
Due to an incorrect mount point specification, the settings specified by the `initContainer` that configures `etcd` users and their permissions are overwritten when using `cilium-cli` to configure a cluster mesh. An attacker who has already gained access to a valid key and certificate for an `etcd` cluster compromised in this manner could then modify state in that `etcd` cluster.
This issue is patched in `cilium-cli` 0.13.2. As a workaround, one may use Cilium's Helm charts to create their cluster.EPSS0.19%MediumCVE-2023-30851chainguard · cilium-1.15 +20 morePotential HTTP policy bypass when using header rules in CiliumCilium is a networking, observability, and security solution with an eBPF-based dataplane. This issue only impacts users who have a HTTP policy that applies to multiple `toEndpoints` AND have an allow-all rule in place that affects only one of those endpoints. In such cases, a wildcard rule will be appended to the set of HTTP rules, which could cause bypass of HTTP policies. This issue has been patched in Cilium 1.11.16, 1.12.9, and 1.13.2.EPSS0.66%MediumCVE-2023-34242chainguard · hubble-ui-backend +3 moreCilium vulnerable to information leakage via incorrect ReferenceGrant handlingCilium is a networking, observability, and security solution with an eBPF-based dataplane. Prior to version 1.13.4, when Gateway API is enabled in Cilium, the absence of a check on the namespace in which a ReferenceGrant is created could result in Cilium unintentionally gaining visibility of secrets (including certificates) and services across namespaces. An attacker on an affected cluster can leverage this issue to use cluster secrets that should not be visible to them, or communicate with services that they should not have access to. Gateway API functionality is disabled by default. This vulnerability is fixed in Cilium release 1.13.4. As a workaround, restrict the creation of `ReferenceGrant` resources to admin users by using Kubernetes RBAC.EPSS0.30%