What the vulnerability does
01Description
The WP Cost Estimation plugin for WordPress is vulnerable to arbitrary file uploads and deletion due to missing file type validation in the lfb_upload_form and lfb_removeFile AJAX actions in versions up to, and including, 9.642. This makes it possible for unauthenticated attackers to upload arbitrary files on the affected sites server which may make remote code execution possible. Additionally, the attacker can also delete files on the server such as database configuration files, subsequently uploading their own database files.
Explanation of Vulnerability in Simple Terms
02Summary
WP Cost Estimation & Payment Forms Builder versions before 9.644 allow unauthenticated attackers to upload files without restriction. An attacker can upload malicious files to the server over the network without needing credentials or user interaction. This enables running arbitrary code on the site and compromising all data.
What an attacker can do
03Attacker Capabilities
Upload malicious files to the server and run their own code on the site.
Potential impact on your site
04Site Impact
Complete site compromise: attackers can read/modify all data, create admin accounts, or take the site offline.
Conditions required to exploit
05Prerequisites
Network access only; no authentication or user interaction required.
Key dates
06Disclosure timeline
January 8, 2026
CVE published
April 8, 2026
Record updated
