This indicates an attack attempt to exploit a SQL Injection Vulnerability in ThinkPHP.
The vulnerability is a result of the application's failure to properly sanitize user input before using it in a SQL query. As a result, a remote attacker can send a crafted query to execute SQL commands on a vulnerable server.
System Compromise: Remote attackers can gain control of vulnerable systems.
Currently we are unaware of any vendor supplied patch or updates available for this issue.