Cilium

By the Year

In 2026 there have been 4 vulnerabilities in Cilium with an average score of 5.7 out of ten. Last year, in 2025 Cilium had 6 security vulnerabilities published. If vulnerabilities keep coming in at the current rate, it appears that number of security vulnerabilities in Cilium in 2026 could surpass last years number. However, the average CVE base score of the vulnerabilities in 2026 is greater by 1.68.

Recent Cilium Security Vulnerabilities

CVE	Date	Vulnerability	Products
CVE-2026-10722	Jun 03, 2026	cilium eBPF int overflow in LoadCollectionSpec before 0.21.0 A 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.	Ebpf
CVE-2026-41520	May 08, 2026	Sensitive Data Leak in cilium-bugtool (pre-1.19.3) Cilium 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.	Cilium
CVE-2026-33726	Mar 27, 2026	Cilium <1.19.2: Ingress Policy bypass via Per-Endpoint routing Cilium 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.	Cilium
CVE-2026-26963	Feb 19, 2026	Cilium 1.18.0-1.18.5: Native Routing/WireGuard Bypass Traffic Cilium 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.	Cilium
CVE-2025-64715	Nov 29, 2025	Cilium eBPF egress SG ID bug: unintended outbound (1.16-1.18) Cilium is a networking, observability, and security solution with an eBPF-based dataplane. Prior to versions 1.16.17, 1.17.10, and 1.18.4, CiliumNetworkPolicys which use egress.toGroups.aws.securityGroupsIds to reference AWS security group IDs that do not exist or are not attached to any network interface may unintentionally allow broader outbound access than intended by the policy authors. In such cases, the toCIDRset section of the derived policy is not generated, which means outbound traffic may be permitted to more destinations than originally intended. This issue has been patched in versions 1.16.17, 1.17.10, and 1.18.4. There are no workarounds for this issue.	Cilium
CVE-2025-32793	Apr 21, 2025	Cilium Wireguard encryption race (1.15.0-1.17.2) leaving packets unencrypted Cilium is a networking, observability, and security solution with an eBPF-based dataplane. Versions 1.15.0 to 1.15.15, 1.16.0 to 1.16.8, and 1.17.0 to 1.17.2, are vulnerable when using Wireguard transparent encryption in a Cilium cluster, packets that originate from a terminating endpoint can leave the source node without encryption due to a race condition in how traffic is processed by Cilium. This issue has been patched in versions 1.15.16, 1.16.9, and 1.17.3. There are no workarounds available for this issue.	Cilium
CVE-2025-30162	Mar 24, 2025	Cilium v1.15-1.17 Egress Bypass via GW LB (fixed v1.15.15+, v1.16.8+, v1.17.2+) Cilium is a networking, observability, and security solution with an eBPF-based dataplane. For Cilium users who use Gateway API for Ingress for some services and use LB-IPAM or BGP for LB Service implementation and use network policies to block egress traffic from workloads in a namespace to workloads in other namespaces, egress traffic from workloads covered by such network policies to LoadBalancers configured by `Gateway` resources will incorrectly be allowed. LoadBalancer resources not deployed via a Gateway API configuration are not affected by this issue. This issue affects: Cilium v1.15 between v1.15.0 and v1.15.14 inclusive, v1.16 between v1.16.0 and v1.16.7 inclusive, and v1.17 between v1.17.0 and v1.17.1 inclusive. This issue is fixed in Cilium v1.15.15, v1.16.8, and v1.17.2. A Clusterwide Cilium Network Policy can be used to work around this issue for users who are unable to upgrade.	Cilium
CVE-2025-30163	Mar 24, 2025	Cilium v1.16/v1.17 NP Bypass (CVE-2025-30163) Cilium is a networking, observability, and security solution with an eBPF-based dataplane. Node based network policies (`fromNodes` and `toNodes`) will incorrectly permit traffic to/from non-node endpoints that share the labels specified in `fromNodes` and `toNodes` sections of network policies. Node based network policy is disabled by default in Cilium. This issue affects: Cilium v1.16 between v1.16.0 and v1.16.7 inclusive and v1.17 between v1.17.0 and v1.17.1 inclusive. This issue is fixed in Cilium v1.16.8 and v1.17.2. Users can work around this issue by ensuring that the labels used in `fromNodes` and `toNodes` fields are used exclusively by nodes and not by other endpoints.	Cilium
CVE-2025-23047	Jan 22, 2025	Cilium Hubble UI CORS Header Data Exposure 1.14-1.16 (fixed 1.14.18-1.16.5) Cilium is a networking, observability, and security solution with an eBPF-based dataplane. An insecure default `Access-Control-Allow-Origin` header value could lead to sensitive data exposure for users of Cilium versions 1.14.0 through 1.14.7, 1.15.0 through 1.15.11, and 1.16.0 through 1.16.4 who deploy Hubble UI using either Cilium CLI or via the Cilium Helm chart. A user with access to a Hubble UI instance affected by this issue could leak configuration details about the Kubernetes cluster which Hubble UI is monitoring, including node names, IP addresses, and other metadata about workloads and the cluster networking configuration. In order for this vulnerability to be exploited, a victim would have to first visit a malicious page. This issue is fixed in Cilium v1.14.18, v1.15.12, and v1.16.5. As a workaround, users who deploy Hubble UI using the Cilium Helm chart directly can remove the CORS headers from the Helm template as shown in the patch from commit a3489f190ba6e87b5336ee685fb6c80b1270d06d.	Cilium
CVE-2025-23028	Jan 22, 2025	Cilium DoS via crafted DNS response 1.14.0-1.16.4 Cilium is a networking, observability, and security solution with an eBPF-based dataplane. A denial of service vulnerability affects versions 1.14.0 through 1.14.7, 1.15.0 through 1.15.11, and 1.16.0 through 1.16.4. In a Kubernetes cluster where Cilium is configured to proxy DNS traffic, an attacker can crash Cilium agents by sending a crafted DNS response to workloads from outside the cluster. For traffic that is allowed but without using DNS-based policy, the dataplane will continue to pass traffic as configured at the time of the DoS. For workloads that have DNS-based policy configured, existing connections may continue to operate, and new connections made without relying on DNS resolution may continue to be established, but new connections which rely on DNS resolution may be disrupted. Any configuration changes that affect the impacted agent may not be applied until the agent is able to restart. This issue is fixed in Cilium v1.14.18, v1.15.12, and v1.16.5. No known workarounds are available.	Cilium