CVE-2026-33726
Cilium L7 proxy may bypass Kubernetes NetworkPolicy for same-node traffic
- Published
- Updated
- Reserved
- Assigned by
- GitHub_M
Description
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.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | Medium5.4 | CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N |
| NVDNVD · Analyzed | 3.1 | Medium4.3 | CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N |
- EPSS (exploitation in 30 days)
- 0.26% · top 83% of all CVEs (6 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.4.
Weakness
Affected products
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- Gogithub.com/cilium/ciliumGHSA-hxv8-4j4r-cqgv (opens in a new tab)
References (6)
- https://github.com/cilium/cilium/security/advisories/GHSA-hxv8-4j4r-cqgv (opens in a new tab)x_refsource_CONFIRM
- https://github.com/cilium/cilium/pull/44693 (opens in a new tab)x_refsource_MISC
- https://docs.cilium.io/en/stable/network/concepts/routing/#routing (opens in a new tab)x_refsource_MISC
- https://docs.cilium.io/en/stable/network/kubernetes/policy/#network-policy (opens in a new tab)x_refsource_MISC
- https://docs.cilium.io/en/stable/network/servicemesh/l7-traffic-management (opens in a new tab)x_refsource_MISC
- https://docs.cilium.io/en/stable/operations/performance/tuning/#ebpf-host-routing (opens in a new tab)x_refsource_MISC
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-hxv8-4j4r-cqgv (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-33726)Record last updated .