CVE-2025-49946 identifies a Reflected Cross-site Scripting (XSS) vulnerability in the 'Auto Login After Registration' plugin developed by Cynob IT Consultancy, affecting versions up to 1.0.0. The vulnerability stems from improper neutralization of user-supplied input during web page generation, which allows an attacker to inject malicious JavaScript code into HTTP responses. When a victim clicks on a specially crafted URL containing malicious payloads, the injected script executes within the victim's browser context. This can lead to theft of session cookies, enabling session hijacking, unauthorized actions on behalf of the user, or redirection to phishing or malware sites. The vulnerability does not require prior authentication, increasing the attack surface, and user interaction is limited to clicking a malicious link. Although no public exploits are currently known, the vulnerability is publicly disclosed and thus susceptible to exploitation once weaponized. The plugin is typically used in WordPress environments to facilitate automatic login immediately after user registration, making it attractive for attackers targeting web applications that rely on this plugin for user onboarding. The lack of a CVSS score necessitates an independent severity assessment based on impact and exploitability factors.

For European organizations, the impact of this vulnerability can be significant, particularly for those relying on WordPress sites that use the 'Auto Login After Registration' plugin. Successful exploitation can compromise user accounts by stealing session tokens or credentials, leading to unauthorized access to sensitive data and services. This can result in data breaches, reputational damage, and potential regulatory penalties under GDPR if personal data is exposed. Additionally, attackers could use the vulnerability to conduct phishing campaigns or distribute malware by redirecting users to malicious sites. The ease of exploitation without authentication and the common use of WordPress in Europe amplify the risk. Organizations in sectors such as e-commerce, education, and government, where user registration and login flows are critical, may face operational disruptions and loss of customer trust.

Organizations should immediately inventory their WordPress installations to identify the presence of the 'Auto Login After Registration' plugin. Since no patch links are currently available, administrators should monitor vendor communications for updates or security patches. In the interim, applying web application firewall (WAF) rules to detect and block reflected XSS payloads targeting this plugin can reduce risk. Implement strict input validation and output encoding on all user-supplied data, especially in registration and login workflows. Deploy Content Security Policies (CSP) to restrict the execution of unauthorized scripts. Educate users to avoid clicking suspicious links and implement multi-factor authentication (MFA) to limit the impact of compromised credentials. Regularly review logs for anomalous activity related to user sessions and registration endpoints. Consider disabling or replacing the vulnerable plugin if immediate patching is not feasible.