This indicates an attack attempt to exploit a SQL Injection Vulnerability in Advantech WebAccess.
The vulnerability is due to an error in the vulnerable application when handling a maliciously crafted request. A remote attacker may be able to exploit this to execute arbitrary code within the context of the application, via a crafted request.
Advantech WebAccess prior to 8.2_20170817
System Compromise: Remote attackers can add, view, delete or modify data in the database of the affected application
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