# CVE-2021-20182: Privilege escalation in openshift

> Attackers with build container access can escalate privileges to cluster admin by exploiting raw device access in the chrooted environment.

- **Severity:** High 8.8 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 23 Feb 2021
- **Updated:** 3 Aug 2024

## What is CVE-2021-20182?

CVE-2021-20182 is a high-severity vulnerability in Redhat Openshift Container Platform, published on 23 Feb 2021. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

A privilege escalation flaw was found in openshift4/ose-docker-builder. The build container runs with high privileges using a chrooted environment instead of runc. If an attacker can gain access to this build container, they can potentially utilize the raw devices of the underlying node, such as the network and storage devices, to at least escalate their privileges to that of the cluster admin. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

Weakness: CWE-552 (Files or Directories Accessible to External Parties)

## Which versions are affected by CVE-2021-20182?

It affects 1 product.


Products: Redhat Openshift Container Platform.

## How do I fix CVE-2021-20182?

No fix has been published for CVE-2021-20182 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-20182 being exploited?

There is no known exploitation of CVE-2021-20182 in the wild and no public exploit code.

## Other vulnerabilities in Redhat Openshift Container Platform

- [CVE-2020-27836](https://insights.sbomify.com/CVE-2020-27836/): Missing authorization in cluster-ingress-operator (critical 9.8)
- [CVE-2018-1085](https://insights.sbomify.com/CVE-2018-1085/): Misconfiguration in openshift-ansible (critical 9.0)
- [CVE-2026-54099](https://insights.sbomify.com/CVE-2026-54099/): Privilege escalation in Red Hat OpenShift Container Platform 4 (high 8.8)
- [CVE-2026-1784](https://insights.sbomify.com/CVE-2026-1784/): Ose-cluster-ingress-operator: remote code execution through haproxy configuration injection (high 8.8)
- [CVE-2019-0542](https://insights.sbomify.com/CVE-2019-0542/): xterm vulnerable to remote code execution (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-20182 and fix it if it is affected.

What it is: CVE-2021-20182 is a high-severity vulnerability in Redhat Openshift Container Platform, published on 23 Feb 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-2021-20182 in the wild and no public exploit code.

Affected product: Redhat Openshift Container Platform. No package-level version data is available, so check the vendor advisory linked from the reference page.

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-2021-20182/ (Markdown: https://insights.sbomify.com/CVE-2021-20182/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-20182
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-20182
- OSV: https://osv.dev/vulnerability/CVE-2021-20182

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-20182/
Summaries are generated and may contain mistakes; the official description above is the record.