CVE-2025-6689 is a stored Cross-Site Scripting (XSS) vulnerability affecting the FL3R Accessibility Suite plugin for WordPress, developed by armandofiore. This vulnerability exists in all versions up to and including 1.4 of the plugin. The root cause is insufficient sanitization and escaping of user-supplied input in the plugin's shortcode handler (fl3raccessibilitysuite). Specifically, authenticated users with contributor-level privileges or higher can inject malicious JavaScript code into pages via shortcode attributes. Because the injected scripts are stored persistently, they execute whenever any user accesses the compromised page, potentially leading to session hijacking, privilege escalation, or other malicious actions. The vulnerability is classified under CWE-79 (Improper Neutralization of Input During Web Page Generation), indicating a failure to properly sanitize input before outputting it in web pages. The CVSS v3.1 base score is 6.4 (medium severity), reflecting a network attack vector with low attack complexity, requiring privileges (authenticated contributor or higher), no user interaction, and impacting confidentiality and integrity with a scope change (the vulnerability affects resources beyond the initially vulnerable component). No known exploits are reported in the wild as of the publication date (June 27, 2025). The absence of available patches at the time of reporting suggests that users must apply mitigations or monitor for updates. This vulnerability is significant because WordPress is widely used across Europe for websites of various organizations, including businesses, public institutions, and NGOs. The FL3R Accessibility Suite plugin is designed to improve website accessibility, making it attractive for organizations aiming to comply with accessibility regulations. An attacker exploiting this vulnerability could inject scripts that steal user credentials, perform actions on behalf of users, or spread malware, thereby compromising website integrity and user trust.

For European organizations, the impact of CVE-2025-6689 can be substantial. Many organizations rely on WordPress for their web presence, including government agencies, educational institutions, and private enterprises. The FL3R Accessibility Suite plugin is likely used by entities focused on accessibility compliance, which is a legal requirement under the EU Web Accessibility Directive and related national laws. Exploitation could lead to unauthorized disclosure of sensitive information (confidentiality impact), manipulation of website content or user data (integrity impact), and erosion of user trust. Although availability is not directly affected, the reputational damage and potential regulatory penalties for failing to secure accessible websites could be severe. The requirement for contributor-level authentication limits exploitation to insiders or compromised accounts, but such access is not uncommon in collaborative content management environments. The scope change in the CVSS vector indicates that the vulnerability can affect resources beyond the plugin itself, potentially impacting other parts of the website or user sessions. This could facilitate further attacks such as privilege escalation or lateral movement within the organization’s web infrastructure. Overall, the vulnerability poses a moderate risk that could escalate if combined with other weaknesses or social engineering attacks.

1. Immediate mitigation should include restricting contributor-level access to trusted users only, minimizing the risk of malicious shortcode injection. 2. Website administrators should monitor and audit user-generated content, especially shortcode attributes, for suspicious scripts or anomalies. 3. Implement Web Application Firewall (WAF) rules to detect and block common XSS payloads targeting the fl3raccessibilitysuite shortcode. 4. Disable or remove the FL3R Accessibility Suite plugin if accessibility features can be temporarily managed through alternative means until a patch is released. 5. Employ Content Security Policy (CSP) headers to restrict the execution of inline scripts and reduce the impact of injected scripts. 6. Regularly update WordPress core and plugins, and subscribe to vendor or security mailing lists to receive timely patch notifications. 7. Conduct user training to raise awareness about the risks of privilege misuse and the importance of secure content management practices. 8. After patch availability, promptly apply updates to the FL3R Accessibility Suite plugin to remediate the vulnerability at its source.