Phase-III: maintaining access / post-exploitation / covering tracks

Maintaining access to the target or keeping a backdoor at the startup is an area of critical concern if you belong to the law enforcement industry. We will discuss advanced persistence mechanisms in the upcoming chapters. However, when it comes to a professional penetration test, post-exploitation tends to be more important than maintaining access. Post-exploitation gathers vitals from the exploited systems, cracks hashes to admin accounts, steals credentials, harvests user tokens, gains privileged access by exploiting local system weaknesses, downloads and uploads files, views processes and applications, and much, much more.

Let us perform and run some quick post-exploitation attacks and scripts:

Running some quick post-exploitation commands such as getuid will find the user who is the owner of the exploited process, which in our case is the administrator. We can also see the process ID of the exploited process by issuing the getpid command. One of the most desirable post-exploitation features is to figure out the ARP details if you need to dig deeper into the network. In meterpreter, you can find ARP details by issuing the arp command as shown in the preceding screenshot.

Next, let's harvest files from the target. However, we are not talking about the general single file search and download. Let's do something out of the box using the file_collector post-exploitation module. What we can do is to scan for certain types of files on the target and download them automatically to our system, as shown in the following screenshot:

In the preceding screenshot, we ran a scan on the Users directory (by supplying a -d switch with the path of the directory) of the compromised system to scan for all the files with the extension .doc and .pptx (using a -f filter switch followed by the search expression). We used a -r switch for the recursive search and -o to output the path of files found to the files file. We can see in the output that we have two files. Additionally, the search expression *.doc|*.pptx means all the files with extension .doc or .pptx, and the | is the OR operator.

Let's download the found files by issuing the command, as illustrated in the following screenshot:

We just provided a -i switch followed by the file files, which contains the full path to all the files at the target. However, we also supplied a -l switch to specify the directory on our system where the files will be downloaded. We can see from the preceding screenshot that we successfully downloaded all the files from the target to our machine.

Covering your tracks in a professional penetration test environment may not be suitable because most of the blue teams use logs generated in the penetration test to identify issues and patterns or write IDS/IPS signatures as well.