CVE-2021-4133 Improper Authorization in Keycloak
An attacker with any user account can create new default users via the admin API even when registration is disabled, bypassing access controls.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2021-4133?
CVE-2021-4133 is a high-severity missing authorization vulnerability in Redhat Keycloak, published on 25 Jan 2022. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
A flaw was found in Keycloak in versions from 12.0.0 and before 15.1.1 which allows an attacker with any existing user account to create new default user accounts via the administrative REST API even when new user registration is disabled.
Weakness: CWE-863
Which versions are affected by CVE-2021-4133?
2 open source packages ship an affected version, including org.keycloak:keycloak-services. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
org.keycloak:keycloak-services Maven | All versions | 15.1.1 |
org.keycloak:keycloak-services Maven | All versions | 15.1.1 |
Linux distribution packages (4)
rh-sso7-keycloak Red Hat:red_hat_single_sign_on:7.5::el7 | All versions | 0:15.0.2-3.redhat_00002.1.el7sso |
rh-sso7-keycloak-server Red Hat:red_hat_single_sign_on:7.5::el7 | All versions | 0:15.0.2-3.redhat_00002.1.el7sso |
rh-sso7-keycloak Red Hat:red_hat_single_sign_on:7.5::el8 | All versions | 0:15.0.2-3.redhat_00002.1.el8sso |
rh-sso7-keycloak-server Red Hat:red_hat_single_sign_on:7.5::el8 | All versions | 0:15.0.2-3.redhat_00002.1.el8sso |
Products include Redhat Keycloak.
How do I fix CVE-2021-4133?
Upgrade org.keycloak:keycloak-services to 15.1.1 or later.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2021-4133 being exploited?
There is no known exploitation of CVE-2021-4133 in the wild and no public exploit code.
Other vulnerabilities in Redhat Keycloak
- CVE-2022-4361 Keycloak vulnerable to cross-site scripting when validating URI-schemes on SAML and OIDC
- CVE-2022-1245 Keycloak vulnerable to privilege escalation on Token Exchange feature
- CVE-2021-20195 keycloak Self Stored Cross-site Scripting vulnerability
- CVE-2019-14910 Keycloak Authentication Error
- CVE-2019-14909 Keycloak Authentication Error
Sources
Also known as GHSA-83x4-9cwr-5487, RHSA-2021:5218, RHSA-2021:5219.