CVE-2024-2419 is a vulnerability identified in Keycloak, an open-source identity and access management solution widely used for single sign-on and authentication services. The flaw lies in the redirect_uri validation logic, which is intended to restrict redirection to explicitly allowed hosts after authentication. Due to improper validation, attackers can bypass these restrictions and redirect users to untrusted, potentially malicious sites. This open redirect vulnerability can be exploited to steal access tokens by tricking users into following crafted URLs, thereby enabling attackers to impersonate legitimate users and gain unauthorized access to protected resources. The vulnerability affects Keycloak versions from the initial release up to 23.0.0 and is similar in nature to CVE-2023-6291, indicating a recurring issue in redirect URI validation. The CVSS 3.1 score of 7.1 reflects a high severity, with network attack vector, low attack complexity, no privileges required, but requiring user interaction. The scope is changed, meaning the vulnerability can affect components beyond the initially targeted system. While no active exploits have been reported, the potential for token theft and session hijacking makes this a critical concern for organizations relying on Keycloak for authentication. The vulnerability underscores the importance of robust input validation and strict enforcement of redirect URI policies in identity management systems.

For European organizations, the exploitation of CVE-2024-2419 could lead to significant security breaches involving unauthorized access to sensitive systems and data. Since Keycloak is commonly used in enterprise environments for managing user identities and access controls, token theft could allow attackers to impersonate users, escalate privileges, and access confidential information or critical infrastructure. This can result in data breaches, disruption of services, and loss of trust. The impact extends to sectors such as finance, healthcare, government, and telecommunications, where identity management is crucial. Additionally, the open redirect can facilitate phishing attacks, increasing the risk of credential compromise. The vulnerability's ease of exploitation without authentication and the requirement of only user interaction make it a practical threat vector. European organizations with large user bases or those integrating Keycloak with cloud services and third-party applications are particularly vulnerable. The potential for cross-border attacks also raises concerns about compliance with GDPR and other data protection regulations, as unauthorized access to personal data could lead to regulatory penalties.

To mitigate CVE-2024-2419, organizations should immediately upgrade Keycloak to a version where the vulnerability is patched once available. Until then, implement strict allowlist policies for redirect URIs, ensuring only trusted domains are permitted. Conduct thorough audits of all configured redirect URIs to remove any unnecessary or overly permissive entries. Employ runtime monitoring and logging to detect unusual redirect patterns or access token requests. Educate users to recognize suspicious URLs and phishing attempts that may exploit this vulnerability. Where possible, implement multi-factor authentication (MFA) to reduce the impact of stolen tokens. Use web application firewalls (WAFs) to block malicious redirect attempts and validate incoming requests. Additionally, consider isolating Keycloak instances and limiting their exposure to the internet to reduce attack surface. Regularly review and update security policies related to identity and access management. Collaborate with Keycloak community and vendors for timely updates and security advisories.