CVE-2025-3910 is a medium-severity vulnerability affecting the Red Hat Build of Keycloak, specifically versions 25.0.0, 26.0.0, and 26.2.0. The vulnerability resides in the org.keycloak.authorization package and involves improper authentication logic that allows users to bypass required actions. One critical example of such a required action is the setup of two-factor authentication (2FA). By exploiting this flaw, an attacker with network access and the ability to interact with the user interface could circumvent security controls intended to enforce multi-factor authentication, thereby weakening the authentication process. The CVSS 3.1 base score is 5.4, reflecting a medium impact with network attack vector, low attack complexity, no privileges required, but requiring user interaction. The vulnerability impacts confidentiality and integrity to a limited extent, as it allows unauthorized circumvention of security policies but does not directly cause denial of service or full system compromise. No known exploits are currently reported in the wild, and no patches or mitigations have been explicitly linked in the provided data. The flaw could be exploited by attackers aiming to gain unauthorized access to protected resources by bypassing 2FA enforcement, potentially leading to unauthorized data access or privilege escalation within environments using affected Keycloak versions for identity and access management.

For European organizations, this vulnerability poses a significant risk especially for those relying on Keycloak as their identity and access management (IAM) solution. Keycloak is widely used in enterprises and public sector organizations across Europe for managing authentication and authorization. The ability to bypass 2FA requirements undermines a critical security control, increasing the risk of unauthorized access to sensitive systems and data. This could lead to data breaches, non-compliance with GDPR and other data protection regulations, and reputational damage. Sectors such as finance, healthcare, government, and critical infrastructure, which often mandate strong authentication mechanisms, are particularly vulnerable. The medium severity rating indicates that while exploitation requires user interaction, the ease of bypassing 2FA could facilitate social engineering or phishing attacks that trick users into enabling the exploit. The lack of known exploits in the wild currently reduces immediate risk but does not eliminate the threat, as attackers may develop exploits once the vulnerability becomes widely known.

Organizations should promptly assess their use of Keycloak versions 25.0.0, 26.0.0, and 26.2.0 and plan to upgrade to patched versions once available from Red Hat. In the absence of an official patch, administrators should implement compensating controls such as enforcing 2FA at the identity provider level outside of Keycloak where possible, or integrating additional authentication gateways that cannot be bypassed. Monitoring authentication logs for unusual patterns or failed 2FA enforcement attempts can help detect exploitation attempts. User education to recognize phishing and social engineering tactics is critical since user interaction is required for exploitation. Additionally, organizations should review and tighten authorization policies and consider multi-layered authentication strategies. Regular vulnerability scanning and penetration testing focused on authentication workflows can help identify if the vulnerability is exploitable in their environment. Coordination with Red Hat support and subscribing to security advisories will ensure timely updates and patches.