{"id":"CVE-2026-84999","published":"2026-10-28T03:17:16.157","lastModified":"2026-10-28T03:17:16.157","description":"The Pie Register Premium plugin for WordPress is vulnerable to Unrestricted File Type Upload in all versions up to, and including, 3.8.4.0 via the piereg_file_upload function. This is due to the plugin performing file type validation via wp_check_filetype and wp_check_filetype_and_ext but never checking whether those validation calls produced errors before move_uploaded_file() is called, combined with no nonce or capability check on the AJAX handler. This makes it possible for unauthenticated attackers to upload files of dangerous types (e.g. PHP scripts) that may be executable, which makes remote code execution possible. The server returns the generated destination filename in the response, giving the attacker the exact path needed to trigger the uploaded file.","cvssScore":9.8,"cvssSeverity":"CRITICAL","cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cwes":["CWE-434"],"vendors":[],"products":[],"references":[{"url":"https://pieregister.com/","tags":[]},{"url":"https://www.wordfence.com/threat-intel/vulnerabilities/id/8385dd30-28e5-4572-8504-2f3e7029bad6?source=cve","tags":[]}],"exploitRefs":[],"hasPoc":false,"ai":{"summary":"The Pie Register Premium WordPress plugin (up to v3.8.4.0) allows unauthenticated attackers to upload arbitrary file types—including dangerous PHP scripts—due to insufficient validation of file uploads and missing security checks on the AJAX handler, enabling potential remote code execution.","exploitability":"Exploitation is trivial for unauthenticated attackers since no authentication, nonce, or capability check is required, and the server returns the exact path of the uploaded file.","blast_radius":"Successful exploitation allows full system compromise via remote code execution on the web server, potentially affecting all data and services hosted on the same server.","remediation":"Upgrade to Pie Register Premium version 3.8.4.1 or later, which contains the vendor's official fix for this vulnerability.","detection":"Look for unexpected POST requests to wp-admin/admin-ajax.php targeting the piereg_file_upload action with file uploads of executable types (e.g., .php), especially from unauthenticated sessions; also monitor for subsequent HTTP GET/POST requests to newly uploaded PHP files whose paths are returned in the upload response.","tags":["rce","file-upload","unrestricted-upload","web","wordpress","auth-bypass"],"model":"garnet-coder","analyzedAt":"2026-10-28T10:02:10.581Z"}}