- Defiant warned of active exploitation of WooCommerce Wholesale Lead Capture Plugin flaw (CVE‑2026‑27540)
- Critical unauthenticated file‑upload bug lets attackers deploy PHP webshells for site takeover
- Patch released in Feb 2026 (v2.0.3.2); Wordfence blocked 100,000+ attacks, users urged to update and check uploads
A critical vulnerability in a popular WooCommerce plugin is being actively exploited to upload malware and possibly take over entire websites, security experts have warned.
The plugin in question is called Wholesale Lead Capture Plugin for WooCommerce. It adds a dedicated registration and onboarding system for wholesale and B2B customers, letting businesses collect company and other custom information, review applications, assign wholesale user roles, and automate registration and onboarding emails.
It is a premium plugin that costs between $99 and $600 and which, according to the WordPress store page, has more than 20,000 active installations.
A thousand victims
The plugin was vulnerable to an unauthenticated arbitrary file-upload flaw which, as the name suggests, allows unauthenticated parties to upload arbitrary files, including PHP webshells and executable code that can result in full site takeover. It is tracked as CVE-2026-27540 and carries a severity score of 9.0/10 (critical).
Versions 2.0.3.1 and older were said to be affected. Version 2.0.3.2, released on February 20, was said to have addressed the bug, meaning the patch has been available for almost half a year. However, WordPress security outfit Defiant said its Wordfence web application firewall blocked more than 100,000 attacks, and Wordfence added that it observed two attack spikes – one between June 4 and 17, and another one between July 1 and August 30.
In these incidents, the attackers were mostly uploading reconnaissance webshells, possibly mapping out the landscape before deploying more serious malware.
“The uploaded shell.php is a PHP webshell that reports host details and provides a browser-based upload form for writing additional malicious files to the site,” the researchers said.
If you are running the plugin, it is advised you update it to the newest version as soon as possible, and check upload directories for unexpected, or recently created, PHP files.
