CVE-2025-48011 is a medium severity vulnerability identified in the Drupal One Time Password (OTP) module, specifically affecting versions prior to 1.3.0. The vulnerability is classified under CWE-288, which pertains to authentication bypass using an alternate path or channel. In this case, the flaw allows an attacker to bypass the intended authentication mechanisms by exploiting an alternate path or channel within the OTP functionality. This could enable unauthorized users to gain access to protected resources or functionality without proper authentication. The vulnerability has a CVSS 3.1 base score of 4.8, indicating a medium level of severity. The vector string (AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N) shows that the attack can be performed remotely over the network without requiring privileges or user interaction, but it requires high attack complexity. The impact affects confidentiality and integrity to a limited extent, with no impact on availability. No known exploits are currently reported in the wild, and no patches have been linked yet. The vulnerability is significant because Drupal is a widely used content management system, and the OTP module is often employed to enhance authentication security by providing one-time passwords. An authentication bypass in this module undermines the security benefits it is supposed to provide, potentially allowing attackers to impersonate legitimate users or escalate privileges within Drupal-based websites or applications.

For European organizations, this vulnerability poses a risk primarily to those using Drupal websites or applications with the One Time Password module enabled and running affected versions. Successful exploitation could lead to unauthorized access to sensitive data, user accounts, or administrative functions, potentially resulting in data breaches, defacement, or further compromise of internal systems. Given the widespread use of Drupal in Europe across government, education, and private sectors, the impact could be material, especially for organizations relying on OTP for multi-factor authentication. The limited confidentiality and integrity impact means attackers may gain access to some data or functionality but are unlikely to cause system-wide outages or data destruction. However, the bypass of authentication controls can facilitate lateral movement or privilege escalation in complex environments. The medium CVSS score and high attack complexity suggest that while exploitation is not trivial, motivated attackers with sufficient resources could leverage this vulnerability. The absence of known exploits in the wild currently reduces immediate risk but does not eliminate the threat, especially as threat actors often develop exploits after public disclosure.

European organizations should prioritize upgrading the Drupal One Time Password module to version 1.3.0 or later as soon as it becomes available to address this vulnerability. Until a patch is released, organizations should consider disabling the OTP module if feasible or restricting access to the affected functionality through network segmentation and strict access controls. Implementing additional layers of authentication, such as hardware tokens or external multi-factor authentication providers, can reduce reliance on the vulnerable OTP module. Monitoring Drupal logs for unusual authentication attempts or access patterns can help detect potential exploitation attempts. Organizations should also ensure their Drupal core and all modules are kept up to date and conduct regular security assessments focused on authentication mechanisms. Employing web application firewalls (WAFs) with rules targeting known Drupal vulnerabilities may provide temporary protection. Finally, organizations should prepare incident response plans specific to authentication bypass scenarios to quickly contain and remediate any compromise.