This indicates an attack attempt to exploit a SQL Injection vulnerability in Joomla! Component Social Factory.
The vulnerability is due to insufficient sanitizing of user supplied inputs in the application when handling a craft HTTP request. A remote attacker may be able exploit this to execute arbitrary code within the context of the application.
Joomla! Component Social Factory 3.8.3
ThePHPFactory Social Factory 3.8.3
System Compromise: Remote attackers can gain control of vulnerable systems.
Apply latest patch or upgrade to the latest version from the vendor.