# CVE-2021-20262: Keycloak Missing authentication for critical function

> Attackers with temporary physical access can take over accounts because Keycloak fails to require re-authentication during password updates.

- **Severity:** Medium 6.8 (`CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 9 Mar 2021
- **Updated:** 3 Aug 2024
- **Also known as:** GHSA-xf46-8vvp-4hxx

## What is CVE-2021-20262?

CVE-2021-20262 is a medium-severity authentication bypass vulnerability in Redhat Keycloak, published on 9 Mar 2021. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A flaw was found in Keycloak 12.0.0 where re-authentication does not occur while updating the password. This flaw allows an attacker to take over an account if they can obtain temporary, physical access to a user’s browser. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability.

Weakness: CWE-306 (Missing Authentication for Critical Functionality)

## Which versions are affected by CVE-2021-20262?

2 open source packages ship an affected version, including org.keycloak:keycloak-core. It affects 2 products.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `org.keycloak:keycloak-core` | Maven | All versions to 12.0.4 | None |
| `org.keycloak:keycloak-core` | Maven | All versions to 12.0.4 | None |

Products: Redhat Keycloak, Redhat Single Sign-On.

## How do I fix CVE-2021-20262?

No fix has been published for CVE-2021-20262 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-20262 being exploited?

There is no known exploitation of CVE-2021-20262 in the wild and no public exploit code.

## Other vulnerabilities in Redhat Keycloak

- [CVE-2022-4361](https://insights.sbomify.com/CVE-2022-4361/): Keycloak vulnerable to cross-site scripting when validating URI-schemes on SAML and OIDC (critical 10.0)
- [CVE-2022-1245](https://insights.sbomify.com/CVE-2022-1245/): Keycloak vulnerable to privilege escalation on Token Exchange feature (critical 9.8)
- [CVE-2021-20195](https://insights.sbomify.com/CVE-2021-20195/): keycloak Self Stored Cross-site Scripting vulnerability (critical 9.6)
- [CVE-2019-14910](https://insights.sbomify.com/CVE-2019-14910/): Keycloak Authentication Error (critical 9.3)
- [CVE-2019-14909](https://insights.sbomify.com/CVE-2019-14909/): Keycloak Authentication Error (critical 9.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-20262 and fix it if it is affected.

What it is: CVE-2021-20262 is a medium-severity authentication bypass vulnerability in Redhat Keycloak, published on 9 Mar 2021. 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-2021-20262 in the wild and no public exploit code.

Affected packages and fixed versions:
- org.keycloak:keycloak-core (Maven): affected all versions up to 12.0.4; no fix listed
- org.keycloak:keycloak-core (Maven): affected all versions up to 12.0.4; 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-2021-20262/ (Markdown: https://insights.sbomify.com/CVE-2021-20262/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-20262
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-20262
- OSV: https://osv.dev/vulnerability/CVE-2021-20262

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-20262/
Summaries are generated and may contain mistakes; the official description above is the record.