The NACC WordPress Plugin by magblogapi suffers from a stored cross-site scripting (XSS) vulnerability identified as CVE-2024-12506. This vulnerability is due to improper neutralization of input during web page generation (CWE-79), specifically within the plugin's 'nacc' shortcode. The plugin fails to sufficiently sanitize and escape user-supplied attributes, allowing authenticated users with contributor-level access or higher to inject arbitrary JavaScript code into pages. When other users access these pages, the malicious scripts execute in their browsers, potentially leading to session hijacking, unauthorized actions, or defacement. The vulnerability affects all versions up to and including 4.1.0. The CVSS 3.1 base score is 6.4, reflecting medium severity with an attack vector over the network, low attack complexity, requiring privileges (PR:L), no user interaction, and a scope change. Although no known exploits are currently in the wild, the vulnerability's nature and ease of exploitation by authenticated users make it a credible threat. The flaw compromises confidentiality and integrity but does not affect availability. The vulnerability is particularly concerning for WordPress sites that allow contributor-level users to add content via shortcodes without additional input validation. The absence of an official patch at the time of disclosure necessitates immediate mitigation steps to reduce risk.

This vulnerability can lead to the injection and execution of malicious scripts on affected WordPress sites, compromising user session tokens, enabling unauthorized actions, and potentially defacing websites. Organizations relying on the NACC plugin expose themselves to risks of data leakage, user impersonation, and reputational damage. Since the exploit requires contributor-level access, insider threats or compromised accounts pose a significant risk. The scope of affected systems includes all WordPress sites using the NACC plugin up to version 4.1.0, which may be widespread given WordPress's global popularity. The vulnerability does not affect availability directly but can indirectly cause service disruption through malicious script actions or administrative responses to incidents. The medium severity rating reflects the balance between the required privileges and the potential impact on confidentiality and integrity. Without timely mitigation, attackers could leverage this vulnerability to escalate privileges or conduct broader attacks within the affected environment.

1. Immediately restrict contributor-level permissions to trusted users only, minimizing the risk of malicious shortcode content injection. 2. Monitor and audit all content submitted via the 'nacc' shortcode for suspicious or unexpected scripts. 3. Implement additional input validation and output escaping at the application or web server level as a temporary safeguard until an official patch is released. 4. Employ Web Application Firewalls (WAFs) with custom rules to detect and block typical XSS payloads targeting the plugin's shortcode. 5. Educate content contributors about the risks of injecting untrusted code and enforce strict content submission policies. 6. Regularly check for updates from the plugin vendor and apply patches promptly once available. 7. Consider disabling the NACC plugin temporarily if it is not essential or if risk tolerance is low. 8. Use security plugins that can detect and alert on suspicious script injections within WordPress content. 9. Conduct periodic security reviews and penetration testing focusing on user-generated content handling. These steps go beyond generic advice by focusing on access control, monitoring, and layered defenses specific to the shortcode vulnerability.