CVE-2025-49858 is a Stored Cross-Site Scripting (XSS) vulnerability classified under CWE-79, affecting the Arconix Shortcodes plugin developed by tychesoftwares. This vulnerability arises from improper neutralization of input during web page generation, allowing malicious actors to inject and store arbitrary scripts within the plugin's shortcode functionality. When a victim accesses a page containing the malicious shortcode, the injected script executes in the context of the victim's browser, potentially leading to session hijacking, credential theft, or unauthorized actions performed with the victim's privileges. The vulnerability affects all versions of Arconix Shortcodes up to and including version 2.1.17. The CVSS 3.1 base score is 6.5 (medium severity), with the vector indicating network attack vector (AV:N), low attack complexity (AC:L), requiring privileges (PR:L), user interaction (UI:R), scope changed (S:C), and low impact on confidentiality, integrity, and availability (C:L/I:L/A:L). Notably, exploitation requires an authenticated user with some privileges and user interaction, but the scope change indicates that the vulnerability can affect resources beyond the initially vulnerable component. No known exploits are currently reported in the wild, and no patches have been linked yet. The vulnerability is significant because Arconix Shortcodes is a popular WordPress plugin used to add various shortcode functionalities, and stored XSS can be leveraged for persistent attacks against site administrators or visitors.

For European organizations, the impact of this vulnerability can be substantial, especially for those relying on WordPress websites that utilize the Arconix Shortcodes plugin. Stored XSS can lead to unauthorized access to user accounts, data leakage, and compromise of administrative functions. This is particularly critical for organizations handling sensitive personal data under GDPR regulations, as exploitation could result in data breaches and subsequent regulatory penalties. Additionally, the ability to execute scripts in the context of authenticated users can facilitate lateral movement within the web application, potentially leading to further compromise. E-commerce platforms, government portals, and financial institutions using this plugin are at heightened risk due to the sensitive nature of their data and the potential reputational damage. The requirement for authenticated access limits the attack surface but does not eliminate risk, as many organizations have multiple users with varying privilege levels. The scope change in the CVSS vector suggests that the vulnerability could impact other components or data beyond the plugin itself, increasing the potential damage.

1. Immediate audit of all WordPress installations within the organization to identify the presence and version of the Arconix Shortcodes plugin. 2. Disable or remove the Arconix Shortcodes plugin if it is not essential to website functionality. 3. If the plugin is required, restrict user roles and permissions to minimize the number of users who can add or modify shortcodes, thereby reducing the risk of exploitation. 4. Implement strict input validation and output encoding on all user-generated content, especially shortcodes, to prevent injection of malicious scripts. 5. Monitor web application logs and user activity for unusual shortcode creation or modification patterns that could indicate exploitation attempts. 6. Employ Content Security Policy (CSP) headers to limit the execution of unauthorized scripts on web pages. 7. Stay alert for official patches or updates from tychesoftwares and apply them promptly once available. 8. Conduct regular security awareness training for users with shortcode editing privileges to recognize and avoid risky behaviors. 9. Consider deploying Web Application Firewalls (WAF) with custom rules to detect and block XSS payloads targeting shortcode parameters. 10. Perform periodic security assessments and penetration testing focusing on shortcode injection vectors.