The Kunze Law plugin for WordPress, widely used for legal content management, suffers from a Stored Cross-Site Scripting (XSS) vulnerability identified as CVE-2025-15486. This vulnerability exists because the plugin fetches HTML content from a remote server and directly injects it into WordPress pages without any sanitization or escaping, violating secure coding practices against CWE-79. The flaw is exploitable only in multi-site WordPress installations or where the unfiltered_html capability is disabled, and requires the attacker to have administrator-level privileges or higher. An authenticated attacker can craft malicious shortcode inputs that embed arbitrary JavaScript, which will execute in the context of any user visiting the affected pages, potentially leading to session hijacking, privilege escalation, or data theft. Moreover, the vulnerability includes a path traversal issue in the shortcode name parameter, allowing attackers to write malicious HTML files to arbitrary writable locations on the server, increasing the risk of persistent backdoors or defacement. The CVSS 3.1 score is 4.4 (medium), reflecting network attack vector, high complexity, required privileges, no user interaction, and limited confidentiality and integrity impact without availability loss. No patches or known exploits are currently reported, but the vulnerability poses a significant risk in environments where the plugin is deployed on multi-site WordPress installations.

For European organizations, this vulnerability can lead to unauthorized script execution within trusted websites, compromising user sessions, stealing sensitive data, or performing unauthorized actions on behalf of users. The path traversal aspect increases risk by allowing attackers to write malicious files, potentially leading to persistent compromise or defacement. Organizations relying on multi-site WordPress installations with the Kunze Law plugin are particularly at risk, especially legal firms, governmental bodies, or institutions publishing legal content. The compromise of administrator accounts could lead to widespread damage across multiple sites in a multi-site environment. Although the vulnerability requires administrator privileges, insider threats or compromised admin credentials could be leveraged by attackers. The medium severity score suggests moderate impact, but the scope in multi-site setups could amplify damage. European data protection regulations (e.g., GDPR) impose strict requirements on protecting personal data, so exploitation could result in regulatory penalties and reputational damage.

1. Immediately audit WordPress installations to identify the presence of the Kunze Law plugin, especially in multi-site environments. 2. Restrict administrator access strictly and enforce strong authentication mechanisms such as MFA to reduce risk of credential compromise. 3. Disable or limit the use of shortcodes from untrusted sources and avoid enabling unfiltered_html capability unless absolutely necessary. 4. If possible, temporarily deactivate the Kunze Law plugin until a vendor patch is released. 5. Monitor web server logs and WordPress activity logs for unusual shortcode usage or file write attempts indicative of exploitation attempts. 6. Implement Web Application Firewall (WAF) rules to detect and block suspicious shortcode parameters or path traversal patterns. 7. Educate administrators on the risks of injecting remote content without validation and encourage secure plugin development practices. 8. Follow up with the vendor for official patches or updates and apply them promptly once available. 9. Conduct regular security assessments and penetration tests focusing on multi-site WordPress configurations.