CVE-2025-4796 is a high-severity vulnerability affecting the Eventin plugin for WordPress, which is widely used for event management, calendar scheduling, booking, ticketing, and registration functionalities. The vulnerability stems from improper authorization checks in the 'Eventin\Speaker\Api\SpeakerController::update_item' function. Specifically, the plugin fails to properly validate the identity or capabilities of users before allowing updates to sensitive account details such as email addresses. This flaw enables attackers with contributor-level or higher permissions—without needing authentication—to change arbitrary users' email addresses, including those of administrators. By altering an administrator's email, the attacker can trigger a password reset process, effectively taking over the administrator's account. The vulnerability is classified under CWE-639 (Authorization Bypass Through User-Controlled Key), indicating a failure to enforce proper access controls based on user input. The CVSS v3.1 score is 8.8 (high), reflecting the vulnerability's network attack vector (AV:N), low attack complexity (AC:L), requiring privileges (PR:L) but no user interaction (UI:N), with high impact on confidentiality, integrity, and availability (C:H/I:H/A:H). No known exploits are currently reported in the wild, but the potential for privilege escalation and full administrative takeover makes this a critical concern for WordPress sites using Eventin up to version 4.0.34. The vulnerability affects all versions up to and including 4.0.34, and no official patch links are provided yet, indicating that mitigation may require manual intervention or plugin updates once available.

For European organizations, this vulnerability poses a significant risk, especially for those relying on WordPress Eventin plugin for managing events, bookings, and registrations. Successful exploitation can lead to complete administrative account takeover, allowing attackers to manipulate event data, disrupt operations, steal sensitive user information, or deploy further malicious payloads within the compromised WordPress environment. This can result in reputational damage, loss of customer trust, financial losses due to disrupted services, and potential regulatory penalties under GDPR for failing to protect personal data. Organizations in sectors such as education, cultural institutions, conference organizers, and public service providers that use Eventin for event management are particularly vulnerable. The ease of exploitation (no user interaction needed and low complexity) increases the likelihood of attacks, potentially targeting high-profile events or organizations with valuable attendee data. Additionally, the ability to escalate privileges from contributor-level accounts means that even less privileged insiders or compromised contributor accounts can be leveraged to gain full control, increasing the threat surface.

European organizations should immediately audit their WordPress installations to identify the presence and version of the Eventin plugin. Until an official patch is released, it is advisable to restrict contributor-level permissions to trusted users only and consider temporarily disabling the Eventin plugin if feasible. Implement strict monitoring and logging of user account changes, particularly email updates and password reset requests. Employ Web Application Firewalls (WAFs) with custom rules to detect and block suspicious API calls targeting the 'update_item' function or unusual email change activities. Organizations should also enforce multi-factor authentication (MFA) for all administrator accounts to mitigate the risk of account takeover even if credentials are compromised. Regular backups of WordPress sites and databases should be maintained to enable quick restoration in case of compromise. Once a patch is available, prioritize immediate updating of the Eventin plugin to the fixed version. Additionally, conduct security awareness training for users with elevated permissions to recognize and report suspicious activities.