Bug TCC "time /s" disables token privileges

[CAM]

Hi,

This has been tested with TCC 36.52.88. In TCC executing the internal TIME /S command changes the enabled state of privileges in the TCC process token.

Before executing TIME /S, whoami /priv reports:

SeChangeNotifyPrivilege - Enabled
SeImpersonatePrivilege - Enabled
SeCreateGlobalPrivilege - Enabled

Execute:

TIME /S

Afterwards, whoami /priv reports all three privileges as Disabled.

This persists for the lifetime of the TCC process and is inherited by subsequently launched processes. This results in DNS/network failures in applications launched from that TCC instance amongst other process limitations.

Expected behaviour: TIME /S should restore the process token's privilege state after temporarily enabling any privilege required to modify the system time.


Here is the detailed output:

C:\Program Files\JPSoft\TCMD36>ping www.jpsoft.com

Pinging www.jpsoft.com [104.26.13.87] with 32 bytes of data:
Reply from 104.26.13.87: bytes=32 time=10ms TTL=58

Ping statistics for 104.26.13.87:
Packets: Sent = 1, Received = 1, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 10ms, Maximum = 10ms, Average = 10ms
Control-C
^C
C:\Program Files\JPSoft\TCMD36>whoami /priv

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

Privilege Name Description State
========================================= ================================================================== ========
SeLockMemoryPrivilege Lock pages in memory Disabled
SeIncreaseQuotaPrivilege Adjust memory quotas for a process Disabled
SeSecurityPrivilege Manage auditing and security log Disabled
SeTakeOwnershipPrivilege Take ownership of files or other objects Disabled
SeLoadDriverPrivilege Load and unload device drivers Disabled
SeSystemProfilePrivilege Profile system performance Disabled
SeSystemtimePrivilege Change the system time Disabled
SeProfileSingleProcessPrivilege Profile single process Disabled
SeIncreaseBasePriorityPrivilege Increase scheduling priority Disabled
SeCreatePagefilePrivilege Create a pagefile Disabled
SeBackupPrivilege Back up files and directories Disabled
SeRestorePrivilege Restore files and directories Disabled
SeShutdownPrivilege Shut down the system Disabled
SeDebugPrivilege Debug programs Disabled
SeSystemEnvironmentPrivilege Modify firmware environment values Disabled
SeChangeNotifyPrivilege Bypass traverse checking Enabled
SeRemoteShutdownPrivilege Force shutdown from a remote system Disabled
SeUndockPrivilege Remove computer from docking station Disabled
SeManageVolumePrivilege Perform volume maintenance tasks Disabled
SeImpersonatePrivilege Impersonate a client after authentication Enabled
SeCreateGlobalPrivilege Create global objects Enabled
SeIncreaseWorkingSetPrivilege Increase a process working set Disabled
SeTimeZonePrivilege Change the time zone Disabled
SeCreateSymbolicLinkPrivilege Create symbolic links Disabled
SeDelegateSessionUserImpersonatePrivilege Obtain an impersonation token for another user in the same session Disabled

C:\Program Files\JPSoft\TCMD36>time /s
System time updated to : Tue 15 Sep 2026 20:35:44

C:\Program Files\JPSoft\TCMD36>ping www.jpsoft.com
Ping request could not find host www.jpsoft.com. Please check the name and try again.

C:\Program Files\JPSoft\TCMD36>whoami /priv

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

Privilege Name Description State
========================================= ================================================================== ========
SeLockMemoryPrivilege Lock pages in memory Disabled
SeIncreaseQuotaPrivilege Adjust memory quotas for a process Disabled
SeSecurityPrivilege Manage auditing and security log Disabled
SeTakeOwnershipPrivilege Take ownership of files or other objects Disabled
SeLoadDriverPrivilege Load and unload device drivers Disabled
SeSystemProfilePrivilege Profile system performance Disabled
SeSystemtimePrivilege Change the system time Disabled
SeProfileSingleProcessPrivilege Profile single process Disabled
SeIncreaseBasePriorityPrivilege Increase scheduling priority Disabled
SeCreatePagefilePrivilege Create a pagefile Disabled
SeBackupPrivilege Back up files and directories Disabled
SeRestorePrivilege Restore files and directories Disabled
SeShutdownPrivilege Shut down the system Disabled
SeDebugPrivilege Debug programs Disabled
SeSystemEnvironmentPrivilege Modify firmware environment values Disabled
SeChangeNotifyPrivilege Bypass traverse checking Disabled
SeRemoteShutdownPrivilege Force shutdown from a remote system Disabled
SeUndockPrivilege Remove computer from docking station Disabled
SeManageVolumePrivilege Perform volume maintenance tasks Disabled
SeImpersonatePrivilege Impersonate a client after authentication Disabled
SeCreateGlobalPrivilege Create global objects Disabled
SeIncreaseWorkingSetPrivilege Increase a process working set Disabled
SeTimeZonePrivilege Change the time zone Disabled
SeCreateSymbolicLinkPrivilege Create symbolic links Disabled
SeDelegateSessionUserImpersonatePrivilege Obtain an impersonation token for another user in the same session Disabled

 

[vefatica]

I get similar results from WHOAMI. But ping does not fail after TIME /S.

v:\> ping www.jpsoft.com

Pinging www.jpsoft.com [104.26.12.87] with 32 bytes of data:
Reply from 104.26.12.87: bytes=32 time=23ms TTL=58
Reply from 104.26.12.87: bytes=32 time=22ms TTL=58
Reply from 104.26.12.87: bytes=32 time=20ms TTL=58
Reply from 104.26.12.87: bytes=32 time=20ms TTL=58

Ping statistics for 104.26.12.87:
    Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 20ms, Maximum = 23ms, Average = 21ms

v:\> time /s
System time updated to : Tue  Sep 15, 2026  16:24:34

v:\> ping www.jpsoft.com

Pinging www.jpsoft.com [104.26.12.87] with 32 bytes of data:
Reply from 104.26.12.87: bytes=32 time=20ms TTL=58
Reply from 104.26.12.87: bytes=32 time=22ms TTL=58
Reply from 104.26.12.87: bytes=32 time=20ms TTL=58
Reply from 104.26.12.87: bytes=32 time=24ms TTL=58

Ping statistics for 104.26.12.87:
    Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 20ms, Maximum = 24ms, Average = 21ms

 

[vefatica]

And, (according to Google AI, perhaps you already know), for WHOAMI /PRIV, "disabled" means you can get it but you have to ask for it. If you couldn't get it, it wouldn't be listed.

 

[CAM]

The network restrictions are likely caused by me running Take Command on Server 2025. They aren't that important as such, its just a demonstration of what happens when the privileges are unexpectedly removed by time /s. I may be able to ask for the privileges back from the system, but the removal is unexpected behavior.

I'm sure I can come up with other examples to demonstrate the unforeseen issues this may cause, if required.

 

[vefatica]

I'm sure I can come up with other examples to demonstrate the unforeseen issues this may cause, if required.

Rex would probably appreciate that.

 

[CAM]

Here is another quick example. Opening global shared memory is affected by the TIME /S privilege change when TCC is running as administrator.

C:\Program Files\JPSoft\TCMD36>echo %@smopen[4096,Global\TCCPrivilegeBefore_%_pid]
2000

C:\Program Files\JPSoft\TCMD36>time /s
System time updated to : Wed 16 Sep 2026 09:15:57

C:\Program Files\JPSoft\TCMD36>echo %@smopen[4096,Global\TCCPrivilegeAfter_%_pid]
0