# CVE-2026-33726: GO-2026-4856 - Cilium L7 proxy may bypass Kubernetes NetworkPolicy for same-node traffic in github.com/cilium/cilium

Source: https://junglewise.ai/threats/cve-2026-33726-cilium-l7-proxy-may-bypass-kubernetes-networkpolicy-for-same-node  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-03-26  
License: CC BY 4.0 with a link back

CVE-2026-33726 · Severity: low · CVSS 3.1 · Published 2026-03-26

Cilium L7 proxy may bypass Kubernetes NetworkPolicy for same-node traffic in github.com/cilium/cilium

Technologies: [github.com/cilium/cilium (Go)](https://junglewise.ai/threats/technologies/github-com-cilium-cilium). Vendors: [Go](https://junglewise.ai/threats/vendors/go).

## Quick answers

**Is CVE-2026-33726 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-33726 being exploited in the wild.

**How severe is CVE-2026-33726?** Low severity, with a CVSS score of 3.1, published 26 March 2026.

**Which products and versions are affected?** github.com/cilium/cilium (Go) SEMVER:introduced=0,fixed=1.17.14, SEMVER:introduced=0,fixed=1.17.14,introduced=1.18.0,fixed=1.18.8,introduced=1.19.0,fixed=1.19.2.

**Is there a fix for CVE-2026-33726?** Yes. github.com/cilium/cilium (Go): upgrade to 1.17.14, 1.19.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2026-33726?** Check whether you run github.com/cilium/cilium (Go) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- github.com/cilium/cilium (Go): upgrade to 1.17.14, 1.19.2 or later

  ```sh
  go get github.com/cilium/cilium@v1.19.2
  ```


## Affected products

- github.com/cilium/cilium (Go) SEMVER:introduced=0,fixed=1.17.14, SEMVER:introduced=0,fixed=1.17.14,introduced=1.18.0,fixed=1.18.8,introduced=1.19.0,fixed=1.19.2

## Identifiers

- CVE-2026-33726
- GHSA-hxv8-4j4r-cqgv
- GO-2026-4856

## Related threats

- [Cilium incorrect authorization in Kubernetes NetworkPolicy ipBlock rules](https://junglewise.ai/threats/cve-2026-56743-cilium-incorrect-authorization-in-kubernetes-networkpolicy)
- [Cilium authorization bypass in Gateway API HTTPRoute mirroring](https://junglewise.ai/threats/cve-2026-56742-cilium-authorization-bypass-in-gateway-api-httproute-mirroring)
- [Cilium world-accessible Envoy admin socket on cluster nodes](https://junglewise.ai/threats/cve-2026-49445-cilium-world-accessible-envoy-admin-socket-on-cluster-nodes)
- [Cilium traffic hijacking via CiliumLocalRedirectPolicy addressMatcher](https://junglewise.ai/threats/cve-2026-53935-cilium-traffic-hijacking-via-ciliumlocalredirectpolicy)
- [Cilium sensitive information disclosure in cilium-bugtool](https://junglewise.ai/threats/cve-2026-41520-cilium-sensitive-information-disclosure-in-cilium-bugtool)