Multiple vulnerabilities in Keycloak

1) Improper Certificate Validation

EUVDB-ID: #VU77752

Risk: Medium

CVSSv4.0: 1.7 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2023-1664

CWE-ID: CWE-295 - Improper Certificate Validation

Exploit availability: No

Description

The vulnerability allows a remote attacker to bypass client certificate validation.

The vulnerability exists due to improper certificate validation when using X509 Client Certificate Authenticatior with the option "Revalidate Client Certificate". A remote attacker with ability to directly connect to Keycloak (e.g. not via the reverse proxy) can bypass certificate validation and gain unauthorized access to the application.

Successful exploitation of the vulnerability requires that there's a configuration error in KC_SPI_TRUSTSTORE_FILE_FILE, which results in accepting any certificate with the logging information of "Cannot validate client certificate trust: Truststore not available".

Mitigation

Install update from vendor's website.

Vulnerable software versions

Keycloak: 10.0.0 - 21.1.1

CPE2.3

• cpe:2.3:a:keycloak:keycloak:19.0.3:*:*:*:*:*:*:*
• cpe:2.3:a:keycloak:keycloak:21.1.1:*:*:*:*:*:*:*

External links

https://bugzilla.redhat.com/show_bug.cgi?id=2182196
https://github.com/keycloak/keycloak/security/advisories/GHSA-5cc8-pgp5-7mpm

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker 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.

2) Authentication Bypass by Spoofing

EUVDB-ID: #VU77767

Risk: Medium

CVSSv4.0: 4.8 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2023-2585

CWE-ID: CWE-290 - Authentication Bypass by Spoofing

Exploit availability: No

Description

The vulnerability allows a remote attacker to bypass authentication process.

The vulnerability exists due to an error within the Keycloak Device Authorisation Grant. A remote attacker can spoof parts of the device flow and use a device_code to retrieve an access token for other OAuth clients.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Keycloak: 10.0.0 - 21.1.1

CPE2.3

External links

https://github.com/keycloak/keycloak/security/advisories/GHSA-f5h4-wmp5-xhg6

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker 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.

3) Cross-site scripting

EUVDB-ID: #VU77750

Risk: Medium

CVSSv4.0: 1.2 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:U/U:Green]

CVE-ID: CVE-2022-4361

CWE-ID: CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Exploit availability: No

Description

The disclosed vulnerability allows a remote attacker to perform cross-site scripting (XSS) attacks.

The vulnerability exists in the SAML or OIDC providers in Keycloak due to insufficient sanitization of user-supplied data passed via the AssertionConsumerServiceURL value or the redirect_uri. A remote attacker can trick the victim to follow a specially crafted link and execute arbitrary HTML and script code in user's browser in context of vulnerable website.

Successful exploitation of this vulnerability may allow a remote attacker to steal potentially sensitive information, change appearance of the web page, perform phishing and drive-by-download attacks.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Keycloak: 10.0.0 - 21.1.1

CPE2.3

External links

https://access.redhat.com/errata/RHSA-2023:3892
https://github.com/keycloak/keycloak/security/advisories/GHSA-3p62-6fjh-3p5h

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker 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.

4) Improper certificate validation

EUVDB-ID: #VU77766

Risk: Medium

CVSSv4.0: 5 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2023-2422

CWE-ID: CWE-295 - Improper Certificate Validation

Exploit availability: No

Description

The vulnerability allows a remote user to bypass authorization process.

The vulnerability exists due to improper certificate validation chain when a Keycloak server is configured to support mTLS authentication for OAuth/OpenID clients. A remote user that possesses a proper certificate can authorize itself as any other client and therefore access data that belongs to other clients.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Keycloak: 10.0.0 - 21.1.1

CPE2.3

External links

https://github.com/keycloak/keycloak/security/advisories/GHSA-3qh5-qqj2-c78f

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.