The Shared Files – Frontend File Upload Form & Secure File Sharing WordPress plugin suffers from a stored cross-site scripting vulnerability (CWE-79) due to improper neutralization of input during web page generation. Specifically, the sanitize_file() function fails to properly sanitize and escape HTML file uploads, enabling unauthenticated attackers to bypass MIME-type checks and inject malicious scripts. These scripts execute in the context of users who access the uploaded HTML files, potentially compromising user data or session integrity. The vulnerability affects all versions up to 1.7.48 and was publicly disclosed on June 3, 2025. The CVSS v3.1 base score is 7.2, reflecting network attack vector, low attack complexity, no privileges or user interaction required, and impacts on confidentiality and integrity with scope change.

Successful exploitation allows unauthenticated attackers to inject and execute arbitrary web scripts in the context of users accessing the malicious HTML files uploaded via the vulnerable plugin. This can lead to theft of sensitive information, session hijacking, or other client-side attacks impacting confidentiality and integrity. There is no indication of availability impact. No known exploits in the wild have been reported at this time.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, users should consider disabling or restricting the use of the vulnerable plugin, especially the file upload functionality, to prevent untrusted HTML file uploads. Monitoring for suspicious file uploads and removing any untrusted HTML files may reduce risk. Avoid accessing uploaded HTML files from untrusted sources.