# CVE-2023-27594: Cilium vulnerable to potential network policy bypass when routing IPv6 traffic > Attackers can bypass network policies by exploiting IPv6 routing misattribution in Cilium when NodePorts are enabled. - **Severity:** Medium 4.2 (`CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N`) - **Exploited in the wild:** Not known - **Login needed:** Not needed - **Attackable:** Local or same network only - **Victim action needed:** Not needed - **Fix available:** Yes - **Published:** 17 Mar 2023 - **Updated:** 25 Feb 2025 - **Also known as:** BIT-cilium-2023-27594, BIT-cilium-operator-2023-27594, BIT-cilium-proxy-2023-27594, BIT-hubble-2023-27594, BIT-hubble-relay-2023-27594, BIT-hubble-ui-2023-27594, BIT-hubble-ui-backend-2023-27594, GHSA-8fg8-jh2h-f2hc, GO-2023-1643 ## What is CVE-2023-27594? CVE-2023-27594 is a medium-severity vulnerability in cilium, published on 17 Mar 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. 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. Weakness: CWE-863 (Incorrect Authorization), CWE-285 (Improper Authorization) ## Which versions are affected by CVE-2023-27594? 14 open source packages ship an affected version, including github.com/cilium/cilium, cilium and cilium-operator. It affects 1 product. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `github.com/cilium/cilium` | Go | All versions | 1.11.15, 1.12.8, 1.13.1 | | `github.com/cilium/cilium` | Go | All versions | 1.11.15 | | `github.com/cilium/cilium` | Go | All versions | 1.11.15 | | `github.com/cilium/cilium` | Go | From 1.12.0 | 1.12.8 | | `github.com/cilium/cilium` | Go | From 1.12.0 | 1.12.8 | | `github.com/cilium/cilium` | Go | From 1.13.0 | 1.13.1 | | `github.com/cilium/cilium` | Go | From 1.13.0 | 1.13.1 | | `cilium` | Bitnami | All versions | 1.11.15, 1.12.8, 1.13.1 | | `cilium-operator` | Bitnami | All versions | 1.11.15, 1.12.8, 1.13.1 | | `cilium-proxy` | Bitnami | All versions | 1.11.15, 1.12.8, 1.13.1 | | `hubble` | Bitnami | All versions | 1.11.15, 1.12.8, 1.13.1 | | `hubble-relay` | Bitnami | All versions | 1.11.15, 1.12.8, 1.13.1 | | `hubble-ui` | Bitnami | All versions | 1.11.15, 1.12.8, 1.13.1 | | `hubble-ui-backend` | Bitnami | All versions | 1.11.15, 1.12.8, 1.13.1 | Products: Cilium Cilium. ## How do I fix CVE-2023-27594? Upgrade github.com/cilium/cilium to a fixed version for your release line: 1.11.15, 1.12.8 or 1.13.1. ## Is CVE-2023-27594 being exploited? There is no known exploitation of CVE-2023-27594 in the wild and no public exploit code. ## Other vulnerabilities in cilium - [CVE-2026-49445](https://insights.sbomify.com/CVE-2026-49445/): Cilium: Sensitive information disclosure and cluster disruption via local Envoy admin socket access (critical 9.2) - [CVE-2022-29178](https://insights.sbomify.com/CVE-2022-29178/): Incorrect Default Permissions in Cilium (high 8.8) - [CVE-2024-28860](https://insights.sbomify.com/CVE-2024-28860/): Insecure IPsec transport encryption in Cilium (high 8.0) - [CVE-2026-41520](https://insights.sbomify.com/CVE-2026-41520/): Cillium exposes sensitive information included in the cilium-bugtool debug archive (high 7.9) - [CVE-2024-37307](https://insights.sbomify.com/CVE-2024-37307/): Cilium leaks sensitive information in cilium-bugtool (high 7.9) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2023-27594 and fix it if it is affected. What it is: CVE-2023-27594 is a medium-severity vulnerability in cilium, published on 17 Mar 2023. It can only be exploited from the same machine or local network, with no action from the victim. Exploitation: There is no known exploitation of CVE-2023-27594 in the wild and no public exploit code. Affected packages and fixed versions: - github.com/cilium/cilium (Go): affected all versions; fixed in 1.11.15, 1.12.8, 1.13.1 - github.com/cilium/cilium (Go): affected all versions; fixed in 1.11.15 - github.com/cilium/cilium (Go): affected all versions; fixed in 1.11.15 - github.com/cilium/cilium (Go): affected from 1.12.0; fixed in 1.12.8 - github.com/cilium/cilium (Go): affected from 1.12.0; fixed in 1.12.8 - github.com/cilium/cilium (Go): affected from 1.13.0; fixed in 1.13.1 - github.com/cilium/cilium (Go): affected from 1.13.0; fixed in 1.13.1 - cilium (Bitnami): affected all versions; fixed in 1.11.15, 1.12.8, 1.13.1 - cilium-operator (Bitnami): affected all versions; fixed in 1.11.15, 1.12.8, 1.13.1 - cilium-proxy (Bitnami): affected all versions; fixed in 1.11.15, 1.12.8, 1.13.1 - hubble (Bitnami): affected all versions; fixed in 1.11.15, 1.12.8, 1.13.1 - hubble-relay (Bitnami): affected all versions; fixed in 1.11.15, 1.12.8, 1.13.1 Task: 1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies. 2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it. 3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead. 4. Run the tests and summarise what changed and why. 5. If nothing in the project is affected, say so and change nothing. Reference: https://insights.sbomify.com/CVE-2023-27594/ (Markdown: https://insights.sbomify.com/CVE-2023-27594/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2023-27594 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-27594 - OSV: https://osv.dev/vulnerability/CVE-2023-27594 --- From sbomify Insights: https://insights.sbomify.com/CVE-2023-27594/ Summaries are generated and may contain mistakes; the official description above is the record.