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 and including 1.0.0. The vulnerability stems from improper neutralization of user-supplied input during the generation of web pages, which allows an attacker to inject malicious JavaScript code into the response sent to users. When a victim interacts with a crafted URL or input, the injected script executes in their browser context, potentially enabling theft of session cookies, redirection to malicious sites, or unauthorized actions performed on behalf of the user. The CVSS 3.1 vector (AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:L) indicates that the attack can be launched remotely over the network without privileges, requires low attack complexity, no privileges, but does require user interaction. The scope is changed, meaning the vulnerability affects components beyond the initially vulnerable module, impacting confidentiality, integrity, and availability to a limited extent. No patches or known exploits are currently documented, but the presence of this vulnerability in a plugin designed to streamline user registration and login processes makes it a valuable target for attackers seeking to compromise user sessions or inject malicious content. The vulnerability is particularly relevant for websites relying on this plugin for user onboarding, as it could undermine user trust and data security.

For European organizations, this vulnerability poses a risk of session hijacking, credential theft, and unauthorized actions performed under the guise of legitimate users. This can lead to data breaches involving personal information, disruption of user services, and reputational damage. Organizations in sectors with strict data protection regulations, such as finance, healthcare, and e-commerce, face heightened compliance risks under GDPR if user data confidentiality or integrity is compromised. The reflected XSS nature means attackers can craft phishing links targeting employees or customers, increasing the likelihood of successful exploitation. Additionally, the vulnerability could be leveraged as a stepping stone for more sophisticated attacks within the network. The impact is amplified for organizations with high volumes of user registrations or those integrating the plugin into critical customer-facing portals. Failure to address this vulnerability promptly could result in regulatory penalties and loss of customer trust across European markets.

1. Immediate upgrade or patching: Monitor Cynob IT Consultancy’s official channels for patches or updates addressing CVE-2025-49946 and apply them promptly. 2. Input validation and output encoding: Implement strict server-side validation of all user inputs and ensure proper HTML entity encoding before rendering inputs in web pages to prevent script injection. 3. Content Security Policy (CSP): Deploy a robust CSP header to restrict the execution of unauthorized scripts and reduce the impact of potential XSS attacks. 4. User interaction awareness: Educate users and staff about the risks of clicking on unsolicited or suspicious links, especially those related to registration or login processes. 5. Web Application Firewall (WAF): Configure WAF rules to detect and block common XSS attack patterns targeting the vulnerable plugin endpoints. 6. Logging and monitoring: Enable detailed logging of web requests and monitor for anomalous activities indicative of exploitation attempts. 7. Disable or replace plugin: If immediate patching is not feasible, consider disabling the vulnerable plugin or replacing it with a more secure alternative that follows secure coding practices. 8. Regular security assessments: Conduct periodic vulnerability scans and penetration tests focusing on web application input handling to detect similar issues proactively.