Saturday, March 22, 2008

Troubleshooting computer accounts in an Active Directory domain

Included are a few esoteric commands and example output of validating Windows Server 2003 computer account objects in an Active Directory domain. The information returned can help troubleshoot Kerberos, the secure channel with the domain, Service Principal Names registered against the computer account, and various bits of local computer information such as group membership and local rights.

Note that this was all run under the system context, the easiest way I know of to get this information, which for network requests translates to networkservice and the AD computer account object.

This was completed by connecting to the console (mstsc /v:%host% /console), and then running:
  • psexec /s /i /d cmd.exe

Note that the console connection is important, as the interactive psexec process is attached to the interactive winlogon console session.

Utilities required:

  • psexec
  • klist
  • setspn
  • nltest
  • whoami

Example output:



C:\>klist tgt

Cached TGT:

ServiceName: krbtgt
TargetName: krbtgt
FullServiceName: COMPUTER$
DomainName: FQDN.DOMAIN
TargetDomainName: FQDN.DOMAIN
AltTargetDomainName: FQDN.DOMAIN
TicketFlags: 0x40e00000
KeyExpirationTime: 1/1/1601 10:00:00
StartTime: 1/16/2008 11:09:20
EndTime: 1/16/2008 21:09:20
RenewUntil: 1/23/2008 11:09:20
TimeSkew: 1/1/1601 10:00:00

C:\>klist tickets

Cached Tickets: (8)

Server: krbtgt/FQDN.DOMAIN@FQDN.DOMAIN
KerbTicket Encryption Type: RSADSI RC4-HMAC(NT)
End Time: 1/16/2008 21:09:20
Renew Time: 1/23/2008 11:09:20


Server: krbtgt/FQDN.DOMAIN@FQDN.DOMAIN
KerbTicket Encryption Type: RSADSI RC4-HMAC(NT)
End Time: 1/16/2008 21:09:20
Renew Time: 1/23/2008 11:09:20


Server: cifs/DC.FQDN.DOMAIN@FQDN.DOMAIN
KerbTicket Encryption Type: RSADSI RC4-HMAC(NT)
End Time: 1/16/2008 21:09:20
Renew Time: 1/23/2008 11:09:20


Server: ldap/DC.FQDN.DOMAIN/FQDN.DOMAIN@FQDN.DOMAIN
KerbTicket Encryption Type: RSADSI RC4-HMAC(NT)
End Time: 1/16/2008 21:09:20
Renew Time: 1/23/2008 11:09:20


Server: host/COMPUTER.FQDN.DOMAIN@FQDN.DOMAIN
KerbTicket Encryption Type: RSADSI RC4-HMAC(NT)
End Time: 1/16/2008 21:09:20
Renew Time: 1/23/2008 11:09:20


Server: COMPUTER$@FQDN.DOMAIN
KerbTicket Encryption Type: RSADSI RC4-HMAC(NT)
End Time: 1/16/2008 21:09:20
Renew Time: 1/23/2008 11:09:20


Server: LDAP/DC.FQDN.DOMAIN/FQDN.DOMAIN@FQDN.DOMAIN
KerbTicket Encryption Type: RSADSI RC4-HMAC(NT)
End Time: 1/16/2008 21:09:20
Renew Time: 1/23/2008 11:09:20


Server: cifs/DC.FQDN.DOMAIN@FQDN.DOMAIN
KerbTicket Encryption Type: RSADSI RC4-HMAC(NT)
End Time: 1/16/2008 21:09:20
Renew Time: 1/23/2008 11:09:20


C:\>setspn -L COMPUTER
Registered ServicePrincipalNames for CN=COMPUTER,OU=Test,DC=domain,DC=com:
HOST/COMPUTER
HOST/COMPUTER.FQDN.DOMAIN

C:\>nltest /sc_query:corp
Flags: 30 HAS_IP HAS_TIMESERV
Trusted DC Name \\DC.FQDN.DOMAIN
Trusted DC Connection Status Status = 0 0x0 NERR_Success
The command completed successfully

C:\>nltest /sc_verify:corp
Flags: b0 HAS_IP HAS_TIMESERV
Trusted DC Name \\DC.FQDN.DOMAIN
Trusted DC Connection Status Status = 0 0x0 NERR_Success
Trust Verification Status = 0 0x0 NERR_Success
The command completed successfully

C:\>whoami /all 

USER INFORMATION 
---------------- 

User Name SID 
=================== ======== 
nt authority\system S-1-5-18 


GROUP INFORMATION 
----------------- 

Group Name Type SID Attributes 
================================ ================ ============ ================================================== 
BUILTIN\Administrators Alias S-1-5-32-544 Enabled by default, Enabled group, Group owner 
Everyone Well-known group S-1-1-0 Mandatory group, Enabled by default, Enabled group 
NT AUTHORITY\Authenticated Users Well-known group S-1-5-11 Mandatory group, Enabled by default, Enabled group 


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

Privilege Name Description State 
=============================== ========================================= ======== 
SeTcbPrivilege Act as part of the operating system Enabled 
SeCreateGlobalPrivilege Create global objects Enabled 
SeTakeOwnershipPrivilege Take ownership of files or other objects Disabled 
SeCreatePagefilePrivilege Create a pagefile Enabled 
SeLockMemoryPrivilege Lock pages in memory Enabled 
SeAssignPrimaryTokenPrivilege Replace a process level token Disabled 
SeIncreaseQuotaPrivilege Adjust memory quotas for a process Disabled 
SeIncreaseBasePriorityPrivilege Increase scheduling priority Enabled 
SeCreatePermanentPrivilege Create permanent shared objects Enabled 
SeDebugPrivilege Debug programs Enabled 
SeAuditPrivilege Generate security audits Enabled 
SeSecurityPrivilege Manage auditing and security log Disabled 
SeSystemEnvironmentPrivilege Modify firmware environment values Disabled 
SeChangeNotifyPrivilege Bypass traverse checking Enabled 
SeBackupPrivilege Back up files and directories Disabled 
SeRestorePrivilege Restore files and directories Disabled 
SeShutdownPrivilege Shut down the system Disabled 
SeLoadDriverPrivilege Load and unload device drivers Disabled 
SeProfileSingleProcessPrivilege Profile single process Enabled 
SeSystemtimePrivilege Change the system time Disabled 
SeUndockPrivilege Remove computer from docking station Disabled 
SeManageVolumePrivilege Perform volume maintenance tasks Enabled 
SeImpersonatePrivilege Impersonate a client after authentication Enabled 



Wayne's World of IT (WWoIT), Copyright 2008 Wayne Martin.

1 comment:

Unknown said...

Congratulation for the great post. Those who come to read your article will find lots of helpful and informative tips.

HP - Pavilion 15.6" Refurbished Laptop - 4GB Memory - 750GB Hard Drive

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