This indicates an attack attempt to exploit an Information Disclosure vulnerability in Schneider Electric SCADA Expert ClearSCADA.
The vulnerability is due to lack of authentication for the default account. A remote attacker can exploit this to gain unauthorized access to sensitive information, via a crafted HTTP request.
Schneider Electric ClearSCADA 2010 prior to R3.2
Schneider Electric SCADA Expert ClearSCADA 2014 prior to R1.1
Information Disclosure: Remote attackers can gain sensitive information from vulnerable systems.
Apply the most recent upgrade or patch from the vendor.