Thrown in at the deep end and need to know what version of SCCM 2012 you are currently running in your environment?
Open up the Configuration Manager Console and check About Configuration Manager to retrieve the version/build information.
for Cumulative updates check the registry at HKLM\SOFTWARE\Microsoft\SMS\Setup\CULevel
The following example shows that CU1 is applied.
The following information will help you determine the version.
System Center 2012 Configuration Manager Beta 2 – 5.00.7561.0000
System Center 2012 Configuration Manager RC1 – 5.00.7678.0000
System Center 2012 Configuration Manager RC2 – 5.00.7703.0000
System Center 2012 Configuration Manager RTM – 5.00.7711.0000
System Center 2012 Configuration Manager CU1 – 5.00.7711.0200
System Center 2012 Configuration Manager CU2 – 5.00.7711.0301
System Center 2012 Configuration Manager SP1 Beta – 5.00.7561.0000
System Center 2012 Configuration Manager SP1 – 5.00.7804.1000
System Center 2012 Configuration Manager SP1 CU1 – 5.00.7804.1202
System Center 2012 Configuration Manager SP1 CU2 – 5.00.7804.1300
System Center 2012 Configuration Manager SP1 CU3 – 5.00.7804.1400
System Center 2012 Configuration Manager SP1 CU4- 5.00.7804.1500
System Center 2012 Configuration Manager SP1 CU5- 5.00.7804.1600
System Center 2012 Configuration Manager R2 – 5.00.7958.1000
System Center 2012 Configuration Manager R2 Hotfix: KB 2905002– 5.00.7958.1101
System Center 2012 Configuration Manager R2 CU1 – 5.00.7958.1203
System Center 2012 Configuration Manager R2 CU2 – 5.00.7958.1303
System Center 2012 Configuration Manager R2 CU3 – 5.00.7958.1401