Improper access control in Keycloak

1) Improper access control

EUVDB-ID: #VU59083

Risk: Low

CVSSv3.1: 3.8 [CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-4133

CWE-ID: CWE-284 - Improper Access Control

Exploit availability: No

Description

The vulnerability allows a remote user to gain unauthorized access to otherwise restricted functionality.

The vulnerability exists due to improper access restrictions within the administrative REST API. A remote user can bypass implemented security restrictions and create new default user accounts, even when new user registration is disabled.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Keycloak: 12.0.0 - 15.1.0

External links

http://bugzilla.redhat.com/show_bug.cgi?id=2033602

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.