CVE-2025-11167 is an Open Redirect vulnerability classified under CWE-601 found in the CM Registration – Tailored tool for seamless login and invitation-based registrations WordPress plugin developed by creativemindssolutions. This vulnerability affects all versions up to and including 2.5.6. The root cause is insufficient validation of the 'redirect_url' parameter, which is used to redirect users after login or registration actions. Because the parameter is not properly sanitized or restricted, attackers can craft URLs that redirect users to arbitrary external websites. An unauthenticated attacker can exploit this by tricking users into clicking maliciously crafted links, leading them to phishing sites or other malicious destinations. The vulnerability does not directly compromise confidentiality but can undermine user trust and integrity by facilitating social engineering attacks. The CVSS 3.1 base score is 4.7, reflecting a medium severity with network attack vector, low attack complexity, no privileges required, but requiring user interaction. The scope is changed (S:C), indicating that the vulnerability affects resources beyond the vulnerable component. No patches or fixes have been published yet, and no known exploits are reported in the wild. This vulnerability is particularly relevant for websites using this plugin for user login and invitation workflows, which are common in community or membership sites. Attackers leveraging this vulnerability could redirect users to malicious sites to harvest credentials, distribute malware, or conduct phishing campaigns.

For European organizations, the impact of CVE-2025-11167 lies primarily in the potential for phishing and social engineering attacks facilitated by malicious redirects. Organizations using the CM Registration plugin on WordPress sites that handle user registrations or invitations may see increased risk of users being redirected to fraudulent sites, potentially leading to credential theft or malware infections. Although the vulnerability does not directly expose sensitive data or allow system compromise, the indirect consequences can include reputational damage, loss of user trust, and increased support costs. Sectors such as education, non-profits, and small to medium enterprises that rely on WordPress for community engagement or membership management are particularly vulnerable. The medium severity score reflects that while exploitation is relatively straightforward, it requires user interaction and does not lead to direct data breaches or system control. However, the changed scope indicates that the impact can extend beyond the plugin itself, affecting the broader user base and potentially other integrated systems if users are redirected to malicious sites that exploit further vulnerabilities.

To mitigate CVE-2025-11167, European organizations should implement the following specific actions: 1) Immediately audit all WordPress sites using the CM Registration plugin to identify affected versions (up to 2.5.6). 2) Restrict or sanitize the 'redirect_url' parameter by implementing server-side validation that only allows redirects to whitelisted, trusted domains or relative URLs within the same site. 3) Employ Web Application Firewalls (WAFs) with rules to detect and block suspicious redirect URL patterns associated with this vulnerability. 4) Educate users and administrators about the risks of clicking on unexpected or suspicious links, especially those involving login or registration workflows. 5) Monitor web server logs and user reports for unusual redirect activity or phishing attempts. 6) Engage with the plugin vendor or community to obtain or contribute patches and updates that fix the validation flaw. 7) Consider temporary disabling or replacing the plugin with alternatives that do not have this vulnerability if immediate patching is not possible. 8) Implement Content Security Policy (CSP) headers to restrict the domains to which the browser can navigate or load resources, reducing the impact of malicious redirects. These measures go beyond generic advice by focusing on parameter validation, user awareness, and layered defenses tailored to this specific vulnerability.