Server-Side Request Forgery (SSRF)
A flaw was found in Keycloak before 12.0.2, where it is possible to force the server to call out an unverified URL using the OIDC parameter request_uri. This flaw allows an attacker to use this parameter to execute a Server-side request forgery (SSRF) attack.
CWE-918 - Server-Side Request Forgery (SSRF)
Server-side request forgery (SSRF) is a weakness that allows an attacker to send an arbitrary request, making it appear that the request was sent by the server. This request may bypass a firewall that would normally prevent direct access to the URL. The impact of this vulnerability can vary from unauthorized access to files and sensitive information to remote code execution.