CVE-2021-3424: Medium severity redhat Single Sign-on vulnerability

Published Feb 26, 2021
·
Updated

A flaw was found in keycloak as shipped in Red Hat Single Sign-On 7.4 where IDN homograph attacks are possible. A malicious user can register himself with a name already registered and trick admin to grant him extra privileges.

Other sources

A flaw was found in keycloak, where IDN homograph attacks are possible. This flaw allows a malicious user to register a name that already exists and then tricking an admin to grant extra privileges. The highest threat from this vulnerability is to integrity.

A flaw was found in keycloak. Internationalized domain name (IDN) homograph attacks may be used to impersonate users.

References:

https://issues.redhat.com/browse/KEYCLOAK-17256

Red Hat

Affected Software

5 affected componentsFixes available
redhat/rh-sso7-keycloak<0:9.0.13-1.redhat_00006.1.el6
0:9.0.13-1.redhat_00006.1.el6
redhat/rh-sso7-keycloak<0:9.0.13-1.redhat_00006.1.el7
0:9.0.13-1.redhat_00006.1.el7
redhat/rh-sso7-keycloak<0:9.0.13-1.redhat_00006.1.el8
0:9.0.13-1.redhat_00006.1.el8
redhat/keycloak<18.0.0
18.0.0
redhat Single Sign-on=7.4

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade redhat/rh-sso7-keycloak to a version that resolves this vulnerability.

    Fixed in 0:9.0.13-1.redhat_00006.1.el6
  2. Upgrade

    Upgrade redhat/rh-sso7-keycloak to a version that resolves this vulnerability.

    Fixed in 0:9.0.13-1.redhat_00006.1.el7
  3. Upgrade

    Upgrade redhat/rh-sso7-keycloak to a version that resolves this vulnerability.

    Fixed in 0:9.0.13-1.redhat_00006.1.el8
  4. Upgrade

    Upgrade redhat/keycloak to a version that resolves this vulnerability.

    Fixed in 18.0.0

Event History

Mar 8, 2021
CVE Published
12:00 AM
Jun 1, 2021
CVE Published
via MITRE·06:43 PM
Data Sourced
via MITRE·06:43 PM
DescriptionWeakness
Data Sourced
via NVD·07:15 PM
DescriptionSeverityWeaknessAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is CVE-2021-3424?

CVE-2021-3424 is a vulnerability in Keycloak, as shipped in Red Hat Single Sign-On 7.4, that allows IDN homograph attacks.

2

What is the severity of CVE-2021-3424?

The severity of CVE-2021-3424 is medium with a CVSS score of 5.3.

3

How does CVE-2021-3424 affect me?

CVE-2021-3424 allows a malicious user to register a name that already exists and trick an admin to grant extra privileges, posing an integrity threat.

4

How can I fix CVE-2021-3424?

To fix CVE-2021-3424, update the affected software to version 18.0.0 for Keycloak or apply the specific security patches provided by Red Hat for Red Hat Single Sign-On 7.4.

5

Where can I find more information about CVE-2021-3424?

You can find more information about CVE-2021-3424 on the CVE website, NIST NVD database, GitHub security advisory, Red Hat Bugzilla, and Red Hat errata page.

Contact

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