If you need to move files, logs, or any kind of program output off a compromised system without disrupting evidentiary data on the disk, use netcat.
On your trusted system:
$ nc -v -l -p 2222 > victim.dump
On the victim's system:
$ <program> | nc <trusted_system> 2222
Where program is the discovery application you're running (e.g. netstat -an).
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