This indicates an attack attempt to exploit a SQL Injection vulnerability in Trend Micro Email Encryption Gateway.
The vulnerability is due to insufficient sanitizing of user supplied inputs in the application when handling a craft HTTP request. A remote attacker can exploit this to send a crafted query to execute SQL commands on a vulnerable server.
Trend Micro Email Encryption Gateway version 5.5 Build 1111 and below
System Compromise: Remote attackers can access or modify data in the database of the affected application
Apply the most recent upgrade or patch from the vendor.