Critical Unauthenticated File Upload Flaw in WooCommerce Wholesale Lead Capture Enables Active PHP Web Shell Attacks
A critical vulnerability tracked as CVE-2026-27540 affects WooCommerce Wholesale Lead Capture versions 2.0.3.1 and earlier, allowing unauthenticated attackers to upload arbitrary files including PHP web shells. The flaw resides in the wwlc_file_upload_handler AJAX action, where the file extension allowlist can be manipulated through the file_settings parameter to accept .php files. Exploitation has been observed in the wild with more than 100,000 blocked attempts since June 2026, including sustained campaigns from repeat IP addresses. The developer released version 2.0.3.2 on 20 February 2026 to address the issue, yet many sites remain unpatched. Organizations are advised to update immediately, audit wp-content/uploads for unexpected PHP files, and monitor admin-ajax.php requests for suspicious activity. In confirmed compromise cases, full remediation requires credential rotation and restoration from verified backups.
HispasecSep 16, 2026Translated from Spanish