CVE-2024-13565 identifies a stored cross-site scripting (XSS) vulnerability in the Simple Map No Api plugin for WordPress, affecting all versions up to and including 1.9. The vulnerability stems from insufficient sanitization and escaping of the 'width' parameter during web page generation. Authenticated attackers with Contributor-level permissions or higher can exploit this flaw by injecting arbitrary JavaScript code into pages that utilize the vulnerable plugin. Because the malicious script is stored persistently, it executes in the context of any user who views the compromised page, potentially leading to session hijacking, credential theft, or unauthorized actions performed on behalf of users. The CVSS 3.1 base score of 6.4 reflects a medium severity, with the attack vector being network-based, requiring low complexity, and only privileges of a Contributor user. No user interaction is needed for the payload to execute once the page is accessed, and the scope is changed due to the potential impact on other users viewing the page. Currently, there are no known public exploits, but the vulnerability is publicly disclosed and should be addressed promptly. The root cause is a failure to properly neutralize input, a classic CWE-79 issue, which can be mitigated by applying proper input validation and output encoding techniques. Given the plugin’s usage in WordPress environments, the vulnerability can affect a wide range of websites, especially those allowing multiple contributors to add or edit content.

The primary impact of this vulnerability is the compromise of confidentiality and integrity for users visiting affected WordPress sites. Attackers can inject malicious scripts that execute in the browsers of site visitors, potentially stealing cookies, session tokens, or other sensitive information. This can lead to account takeover, unauthorized actions, or further exploitation of the site or its users. Since the vulnerability requires Contributor-level access, it also highlights risks associated with privilege management and insider threats. The availability impact is minimal as the vulnerability does not directly cause denial of service. However, reputational damage and loss of user trust can be significant for organizations running affected sites. The scope of impact extends to all users who access the injected pages, making it a multi-user risk. Organizations with multiple contributors or user-generated content are particularly vulnerable. The medium CVSS score reflects the moderate ease of exploitation and the potential for impactful consequences if exploited.

To mitigate this vulnerability, organizations should first update the Simple Map No Api plugin to a patched version once available. In the absence of an official patch, immediate steps include implementing strict input validation on the 'width' parameter to allow only expected numeric or predefined values. Additionally, output encoding should be applied to any data rendered on web pages to prevent script execution. Restrict Contributor-level permissions to trusted users only and review user roles to minimize the risk of malicious input. Employ Web Application Firewalls (WAFs) with rules to detect and block typical XSS payloads targeting the plugin parameters. Regularly audit and monitor site content for unauthorized script injections. Educate content contributors about safe input practices and the risks of injecting untrusted content. Finally, maintain regular backups and incident response plans to quickly recover from any exploitation attempts.