With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
ccmHistoryEventTerminalUser
Cisco Configuration Management History Event Terminal User
1.3.6.1.4.1.9.9.43.1.1.6.1.8
If ccmHistoryEventCommandSource is 'commandLine', the name of the logged in user. The length is zero if not available or not applicable.
Back to CISCO-CONFIG-MAN-MIB MIB page.
IPHost Network monitor allows you to monitor ccmHistoryEventTerminalUser on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco firewalls right now.