CVE-2025-48012 is an authentication bypass vulnerability classified under CWE-294, affecting the Drupal One Time Password (OTP) module versions prior to 1.3.0. The vulnerability arises due to a capture-replay weakness in the OTP mechanism, allowing an attacker to reuse intercepted authentication tokens to bypass authentication controls. Specifically, an attacker who can capture a valid OTP token transmitted during a legitimate authentication attempt can replay this token to gain unauthorized access to remote services protected by the vulnerable OTP implementation. This flaw compromises the integrity of the authentication process by failing to properly validate the uniqueness or freshness of OTP tokens, thereby enabling remote attackers to impersonate legitimate users without needing valid credentials or user interaction. The vulnerability has a CVSS 3.1 base score of 4.8 (medium severity), reflecting its network attack vector, high attack complexity, no privileges required, and no user interaction needed. The impact primarily affects confidentiality and integrity, as unauthorized access can lead to data exposure or manipulation, but does not directly affect availability. No known exploits are currently reported in the wild, and no patches are linked yet, indicating that mitigation may rely on updates from the Drupal project or configuration workarounds. Given Drupal's widespread use in web content management and the critical role of OTP in multi-factor authentication, this vulnerability poses a significant risk to organizations relying on this module for secure access control.

For European organizations, the impact of CVE-2025-48012 can be substantial, particularly for those utilizing Drupal-based web applications with the vulnerable OTP module enabled for authentication. Successful exploitation allows attackers to bypass multi-factor authentication, potentially leading to unauthorized access to sensitive internal systems, customer data, or administrative interfaces. This can result in data breaches, intellectual property theft, and reputational damage. Sectors such as government, finance, healthcare, and critical infrastructure, which often deploy Drupal for public-facing portals or internal applications, are at heightened risk. The ability to remotely bypass authentication without user interaction or privileges lowers the barrier for attackers, increasing the likelihood of targeted attacks or automated exploitation attempts once the vulnerability becomes widely known. Additionally, compliance with GDPR and other data protection regulations may be jeopardized if unauthorized access leads to personal data exposure, resulting in legal and financial penalties.

To mitigate this vulnerability, European organizations should prioritize the following actions: 1) Immediately audit all Drupal installations to identify the presence and version of the One Time Password module. 2) Apply vendor-supplied patches or upgrade the OTP module to version 1.3.0 or later as soon as they become available. 3) In the absence of patches, consider temporarily disabling the OTP module or replacing it with alternative multi-factor authentication solutions that do not exhibit this vulnerability. 4) Implement network-level protections such as IP whitelisting, VPN access, or web application firewalls (WAFs) to restrict access to authentication endpoints and detect replay attack patterns. 5) Monitor authentication logs for repeated or suspicious OTP token usage indicative of replay attacks. 6) Educate users and administrators about the risk and encourage strong password policies and additional security layers beyond OTP where feasible. 7) Engage in threat intelligence sharing with industry peers and national cybersecurity centers to stay informed about emerging exploit attempts and remediation strategies.