CVE-2025-13835 is a stored Cross-site Scripting (XSS) vulnerability identified in the Arconix Shortcodes plugin developed by Tyche Softwares, affecting versions up to 2.1.19. The vulnerability stems from improper neutralization of input during web page generation, classified under CWE-79. This flaw allows an attacker with low privileges (PR:L) to inject malicious scripts that are stored and later executed in the context of other users, requiring user interaction (UI:R) to trigger. The vulnerability has a CVSS 3.1 base score of 6.5, indicating medium severity, with an attack vector of network (AV:N), low attack complexity (AC:L), and scope change (S:C), meaning the vulnerability can affect resources beyond the initially vulnerable component. The impact includes limited confidentiality, integrity, and availability loss, as malicious scripts can steal session tokens, manipulate page content, or perform unauthorized actions on behalf of authenticated users. No public exploits or patches are currently available, increasing the urgency for proactive defense. The vulnerability is particularly relevant for WordPress sites using the Arconix Shortcodes plugin, commonly employed to add shortcode functionalities to websites. Since stored XSS can be leveraged for persistent attacks, it poses a significant risk to user trust and data security.

For European organizations, this vulnerability could lead to unauthorized access to sensitive information, session hijacking, and potential defacement or manipulation of web content, impacting customer trust and regulatory compliance, especially under GDPR. Organizations in sectors such as e-commerce, government, and healthcare that rely on WordPress and the Arconix Shortcodes plugin are at heightened risk. The compromise of user accounts or administrative privileges through XSS could lead to broader network infiltration or data breaches. Additionally, the persistent nature of stored XSS increases the risk of widespread impact across multiple users. The medium severity suggests that while the vulnerability is exploitable, it requires some user interaction and low privileges, which somewhat limits the attack surface but does not eliminate significant risk. European entities must consider the reputational and operational impacts, including potential fines for data breaches under European data protection laws.

1. Immediately audit all WordPress sites for the presence of the Arconix Shortcodes plugin and identify affected versions. 2. Restrict user input fields that interact with the plugin to trusted users only, minimizing exposure to untrusted input. 3. Implement strict Content Security Policies (CSP) to limit the execution of unauthorized scripts. 4. Employ Web Application Firewalls (WAF) with rules to detect and block XSS payloads targeting this plugin. 5. Monitor logs and user activity for unusual behavior indicative of XSS exploitation attempts. 6. Educate users and administrators about the risks of clicking on suspicious links or interacting with untrusted content. 7. Prepare to apply vendor patches or updates as soon as they are released, and consider temporary disabling or replacing the plugin if feasible. 8. Conduct regular security assessments and penetration tests focusing on XSS vulnerabilities in web applications.