AEM Forms SP6 add-on for AEM 6.5.6.0 and Forms add-on package for AEM 6.4 Service Pack 8 Cumulative Fix Pack 2 (6.4.8.2) have a blind Server-Side Request Forgery (SSRF) vulnerability. This vulnerability could be exploited by an unauthenticated attacker to gather information about internal systems that reside on the same network.
https://helpx.adobe.com/security/products/experience-manager/apsb20-72.html