# CVE-2020-8554: Kubernetes man in the middle using LoadBalancer or ExternalIPs

> Attackers with service creation privileges can intercept traffic by setting external IPs or patching LoadBalancer status, requiring API server updates.

- **Severity:** Medium 6.3 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 21 Jan 2021
- **Updated:** 1 Jun 2026
- **Also known as:** AZL-31696, AZL-31731, AZL-34893, AZL-35135, DEBIAN-CVE-2020-8554, GHSA-j9wf-vvm6-4r9w, MINI-45wf-rj4q-954c, MINI-99pr-pcpc-28fv, MINI-9gv3-q5w9-g939, MINI-cg84-h9rw-qp9p, MINI-cvvg-wf97-99mr, MINI-jq26-hqvx-4fhw, MINI-m9fm-fx9q-p38x, MINI-p3cx-827f-6cwx, MINI-p795-gc5c-58qg, MINI-rv8h-r558-g388, MINI-v2v9-qc6q-3h55, MINI-vjp8-rq2q-hm9c

## What is CVE-2020-8554?

CVE-2020-8554 is a medium-severity missing authorization vulnerability in Kubernetes Kubernetes, published on 21 Jan 2021. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Kubernetes API server in all versions allow an attacker who is able to create a ClusterIP service and set the spec.externalIPs field, to intercept traffic to that IP address. Additionally, an attacker who is able to patch the status (which is considered a privileged operation and should not typically be granted to users) of a LoadBalancer service can set the status.loadBalancer.ingress.ip to similar effect.

Weakness: CWE-283 (Unverified Ownership)

## Which versions are affected by CVE-2020-8554?

2 open source packages ship an affected version, including k8s.io/kubernetes. It affects 4 products.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `k8s.io/kubernetes` | Go | All versions to 1.22.0 | None |
| `k8s.io/kubernetes` | Go | All versions to 1.22.0 | None |

Products: Kubernetes Kubernetes, Oracle Communications Cloud Native Core Network Slice Selection Function, Oracle Communications Cloud Native Core Policy, Oracle Communications Cloud Native Core Service Communication Proxy.

## How do I fix CVE-2020-8554?

Apply the vendor's patch.

## Is CVE-2020-8554 being exploited?

There is no known exploitation of CVE-2020-8554 in the wild and no public exploit code.

Public exploit code:

- CVE-2020-8554: Man in the middle using LoadBalancer or ExternalIPs (github_poc): https://github.com/rancher/externalip-webhook
- Mitigate CVE-2020-8554 with Policy Controller in Anthos (github_poc): https://github.com/jrmurray000/CVE-2020-8554
- Prisma Cloud Compute Admission rules to mitigate Kubernetes CVE-2020-8554 (github_poc): https://github.com/twistlock/k8s-cve-2020-8554-mitigations
- https://github.com/Dviejopomata/CVE-2020-8554 (github_poc): https://github.com/Dviejopomata/CVE-2020-8554
- https://github.com/alebedev87/gatekeeper-cve-2020-8554 (github_poc): https://github.com/alebedev87/gatekeeper-cve-2020-8554

## Other vulnerabilities in Kubernetes Kubernetes

- [CVE-2018-1002105](https://insights.sbomify.com/CVE-2018-1002105/): Privilege Escalation in Kubernetes (critical 9.8)
- [CVE-2017-1000056](https://insights.sbomify.com/CVE-2017-1000056/): Kubernetes Privilege Escalation (critical 9.8)
- [CVE-2016-1906](https://insights.sbomify.com/CVE-2016-1906/): Authorization bypass in Openshift (critical 9.8)
- [CVE-2023-3676](https://insights.sbomify.com/CVE-2023-3676/): Kubernetes - Windows nodes - Insufficient input sanitization leads to privilege escalation (high 8.8)
- [CVE-2023-3955](https://insights.sbomify.com/CVE-2023-3955/): Kubernetes - Windows nodes - Insufficient input sanitization leads to privilege escalation (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-8554 and fix it if it is affected.

What it is: CVE-2020-8554 is a medium-severity missing authorization vulnerability in Kubernetes Kubernetes, published on 21 Jan 2021. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2020-8554 in the wild and no public exploit code.

Affected packages and fixed versions:
- k8s.io/kubernetes (Go): affected all versions up to 1.22.0; no fix listed
- k8s.io/kubernetes (Go): affected all versions up to 1.22.0; no fix listed

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-2020-8554/ (Markdown: https://insights.sbomify.com/CVE-2020-8554/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-8554
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-8554
- OSV: https://osv.dev/vulnerability/CVE-2020-8554

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-8554/
Summaries are generated and may contain mistakes; the official description above is the record.