Fluent Forms Pro 6.2.7 — CVE-2026-73532 (Critical)

Summary

Fluent Forms Pro 6.2.7 contains an embedded malicious code vulnerability introduced via a tampered plugin build served through a decommissioned update server. The tampered build introduced a rogue PHP file (libs/class-license-sync.php), loaded via a require_once directive added to fluentformpro.php, that established a backdoor REST API endpoint, dropped persistent PHP files in mu-plugins and uploads directories, installed a passwordless administrator account, and registered scheduled tasks that survived plugin removal.

Why it matters

This CVE carries a CRITICAL severity rating (CVSS 9.8) in Fluent Forms Pro 6.2.7. Patch or mitigate promptly.

Operator check

Review CVE-2026-73532 in your asset inventory. Apply patches per vendor guidance and verify Forms Pro 6.2.7 is not exposed. CVSS score: 9.8.

Sources