T1547.003SubTechniquepersistenceprivilege-escalationagent-callable
T1547.003Time Providers
Sub-technique of T1547
Platforms: Windows
ATT&CK version: 14.1
What it is
Adversaries may abuse time providers to execute DLLs when the system boots. The Windows Time service (W32Time) enables time synchronization across and within domains.(Citation: Microsoft W32Time Feb 2018) W32Time time providers are responsible for retrieving time stamps from hardware/network resources and outputting these values to other network clients.(Citation: Microsoft TimeProvider)
Time providers are implemented as dynamic-link libraries (DLLs) that are registered in the subkeys of <code>HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\W32Time\TimeProviders\</code>.(Citation: Microsoft TimeProvider) The time provider manager, directed by the service control manager, loads and starts time providers listed and enabled under this key at system startup and/or whenever parameters are changed.(Citation: Microsoft TimeProvider)
Adversaries may abuse this architecture to establish persistence, specifically by registering and enabling a malicious DLL as a time provider. Administrator privileges are required for time provider registration, though execution will run in context of the Local Service account.(Citation: Github W32Time Oct 2017)
ATT&CK tactics· 2
References
- https://attack.mitre.org/techniques/T1547/003
- https://github.com/scottlundgren/w32time
- https://docs.microsoft.com/windows-server/networking/windows-time-service/windows-time-service-tools-and-settings
- https://docs.microsoft.com/windows-server/networking/windows-time-service/windows-time-service-top
- https://msdn.microsoft.com/library/windows/desktop/ms725475.aspx
- https://technet.microsoft.com/en-us/sysinternals/bb963902