CVE-2024-11786 is a stored Cross-Site Scripting (XSS) vulnerability identified in the WordPress plugin 'Login with Vipps and MobilePay' developed by wphostingdev. This vulnerability affects all versions up to and including 1.3.3. The root cause is insufficient sanitization and escaping of user-supplied attributes within the plugin's 'continue-with-vipps' shortcode. Authenticated attackers with contributor-level privileges or higher can exploit this flaw by injecting arbitrary JavaScript code into pages generated by the plugin. When other users visit these compromised pages, the injected scripts execute in their browsers, potentially allowing attackers to steal session cookies, perform actions on behalf of users, or escalate privileges. The vulnerability does not require user interaction beyond visiting the infected page and does not affect availability but impacts confidentiality and integrity. The CVSS v3.1 base score is 6.4 (medium severity), reflecting network attack vector, low attack complexity, and privileges required. No public exploits have been reported yet, but the vulnerability is significant due to the widespread use of WordPress and the plugin's role in authentication flows. The vulnerability was published on November 28, 2024, and assigned by Wordfence. No official patches have been linked yet, so mitigation relies on configuration and monitoring until updates are available.

This vulnerability can lead to significant security risks for organizations using the affected plugin, especially those relying on WordPress for customer-facing or internal portals. Exploitation allows attackers with contributor-level access to inject persistent malicious scripts, compromising the confidentiality of user sessions and potentially enabling privilege escalation or unauthorized actions. This can result in data theft, defacement, or unauthorized access to sensitive areas of the website. Since the plugin handles login flows with Vipps and MobilePay, which are popular payment and authentication services in certain regions, exploitation could undermine user trust and lead to financial fraud or reputational damage. The scope includes any WordPress site using this plugin version, which may be numerous given WordPress's market share. The lack of known exploits reduces immediate risk but does not eliminate the threat, especially as the vulnerability is publicly disclosed. Organizations with contributor-level users or higher should be particularly cautious, as these roles can trigger the exploit. The medium severity rating reflects moderate impact and ease of exploitation, but the potential for chained attacks or targeted campaigns could elevate risk in high-value environments.

1. Immediately review and restrict user roles to minimize the number of users with contributor-level or higher privileges, limiting potential attackers. 2. Monitor and audit all pages using the 'continue-with-vipps' shortcode for unauthorized script injections or unexpected content changes. 3. Implement Web Application Firewall (WAF) rules to detect and block suspicious script payloads targeting the vulnerable shortcode parameters. 4. Apply strict input validation and output encoding on all user-supplied attributes related to the shortcode, either by updating the plugin code manually or using security plugins that enforce sanitization. 5. Stay alert for official patches or updates from the plugin vendor and apply them promptly once available. 6. Educate site administrators and content contributors about the risks of injecting untrusted content and enforce secure content management practices. 7. Consider temporarily disabling or replacing the plugin if immediate patching is not possible, especially on high-risk or public-facing sites. 8. Conduct regular security scans and penetration tests focusing on XSS vulnerabilities in WordPress plugins and themes.