An open redirect vulnerability was found in Keycloak. A specially crafted URL can be constructed where the referrer and referrer_uri parameters are made to trick a user to visit a malicious webpage. A trusted URL can trick users and automation into believing that the URL is safe, when, in fact, it redirects to a malicious server. This issue can result in a victim inadvertently trusting the destination of the redirect, potentially leading to a successful phishing attack or other types of attacks. Once a crafted URL is made, it can be sent to a Keycloak admin via email for example. This will trigger this vulnerability when the user visits the page and clicks the link. A malicious actor can use this to target users they know are Keycloak admins for further attacks. It may also be possible to bypass other domain-related security checks, such as supplying this as a OAuth redirect uri. The malicious actor can further obfuscate the redirect_uri using URL encoding, to hide the text of the actual malicious website domain.
Published: 2024-09-09
Updated: 2024-10-01
Base Score: 6.4
Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:N
Severity: Medium
Base Score: 6.1
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Severity: Medium
Base Score: 4.8
Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
Severity: Medium
EPSS: 0.00106