CVE-2025-13835 is a Stored Cross-Site Scripting (XSS) vulnerability classified under CWE-79, affecting the Arconix Shortcodes plugin developed by Tyche Softwares, specifically versions up to 2.1.19. The vulnerability stems from improper neutralization of input during web page generation, meaning that user-supplied data is not adequately sanitized or encoded before being rendered in the HTML output. This flaw allows an attacker with low privileges (PR:L) to inject malicious JavaScript code that is stored persistently on the affected website. The attack requires user interaction (UI:R), such as a victim visiting a crafted page or interacting with malicious content, to trigger the execution of the injected script. The CVSS v3.1 base score is 6.5, reflecting a medium severity level, with an attack vector of network (AV:N), low attack complexity (AC:L), partial impact on confidentiality, integrity, and availability (C:L/I:L/A:L), and scope change (S:C), indicating that the vulnerability can affect components beyond the initially vulnerable module. Stored XSS can lead to session hijacking, defacement, unauthorized actions on behalf of users, or distribution of malware. Although no known exploits are currently reported in the wild and no official patches have been released, the vulnerability poses a tangible risk to websites using this plugin, particularly those with user-generated content or administrative interfaces accessible to multiple users. The plugin is commonly used in WordPress environments to add shortcode functionalities, often in e-commerce or content-heavy sites, increasing the potential attack surface.

For European organizations, the impact of CVE-2025-13835 can be significant, especially for those relying on WordPress sites with the Arconix Shortcodes plugin. Exploitation could lead to unauthorized access to user sessions, data leakage, or defacement of public-facing websites, undermining customer trust and potentially violating data protection regulations such as GDPR. The partial compromise of confidentiality and integrity could expose sensitive customer or business data. Availability impacts, while limited, could disrupt service continuity if exploited to inject disruptive scripts. Organizations in sectors like e-commerce, finance, and public services, which often use WordPress plugins extensively, may face reputational damage and regulatory scrutiny. The requirement for low privileges and user interaction lowers the barrier for exploitation but also limits automated mass exploitation. However, targeted attacks against high-value European entities remain a concern, especially in countries with high WordPress market penetration and active cyber threat landscapes.

To mitigate CVE-2025-13835 effectively, European organizations should: 1) Monitor for and apply official patches or updates from Tyche Softwares as soon as they become available. 2) Implement strict input validation and output encoding on all user-supplied data, particularly in shortcode parameters and content fields. 3) Employ a robust Content Security Policy (CSP) to restrict the execution of unauthorized scripts and reduce the impact of XSS attacks. 4) Limit user privileges to the minimum necessary, especially for users who can submit content or interact with shortcodes. 5) Conduct regular security audits and penetration testing focusing on web application vulnerabilities, including XSS. 6) Educate users and administrators about the risks of interacting with untrusted content. 7) Consider disabling or replacing the Arconix Shortcodes plugin if immediate patching is not feasible, especially on high-risk or critical websites. 8) Use web application firewalls (WAFs) configured to detect and block XSS payloads targeting this plugin.