// For flags

CVE-2021-3424

keycloak: Internationalized domain name (IDN) homograph attack to impersonate users

Severity Score

5.3
*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

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.

Se ha encontrado un fallo en keycloak, tal y como es enviado en Red Hat Single Sign-On versión 7.4, en el que son posibles los ataques de homografía IDN. Un usuario malicioso puede registrarse con un nombre ya registrado y engañar al administrador para que le conceda privilegios adicionales

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.

Red Hat Single Sign-On 7.4 is a standalone server, based on the Keycloak project, that provides authentication and standards-based single sign-on capabilities for web and mobile applications. This release of Red Hat Single Sign-On 7.4.7 serves as a replacement for Red Hat Single Sign-On 7.4.6, and includes bug fixes and enhancements, which are documented in the Release Notes document linked to in the References. Issues addressed include an information leakage vulnerability.

*Credits: N/A
CVSS Scores
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
Low
Availability
None
Attack Vector
Network
Attack Complexity
Low
Authentication
None
Confidentiality
None
Integrity
Partial
Availability
None
* Common Vulnerability Scoring System
SSVC
  • Decision:-
Exploitation
-
Automatable
-
Tech. Impact
-
* Organization's Worst-case Scenario
Timeline
  • 2021-03-08 CVE Reserved
  • 2021-05-20 CVE Published
  • 2024-08-03 CVE Updated
  • 2025-03-30 EPSS Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-287: Improper Authentication
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Redhat
Search vendor "Redhat"
 Single Sign-on
Search vendor "Redhat" for product "Single Sign-on"
 7.4
Search vendor "Redhat" for product "Single Sign-on" and version "7.4"
-
Affected