Adversaries may modify or add LSASS drivers to obtain persistence on compromised systems. The Windows security subsystem is a set of components that manage and enforce the security policy for a computer or domain. The Local Security Authority (LSA) is the main component responsible for local security policy and user authentication. The LSA includes multiple dynamic link libraries (DLLs) associated with various other security functions, all of which run in the context of the LSA Subsystem Service (LSASS) lsass.exe process.(Citation: Microsoft Security Subsystem)

Adversaries may target LSASS drivers to obtain persistence. By either replacing or adding illegitimate drivers (e.g., [Hijack Execution Flow](https://attack.mitre.org/techniques/T1574)), an adversary can use LSA operations to continuously execute malicious payloads.
LSASS Driver
source_name: mitre-attack  url: https://attack.mitre.org/techniques/T1547/008  external_id: T1547.008     source_name: Microsoft LSA Protection Mar 2014  description: Microsoft. (2014, March 12). Configuring Additional LSA Protection. Retrieved November 27, 2017.  url: https://technet.microsoft.com/library/dn408187.aspx     source_name: Microsoft DLL Security  description: Microsoft. (n.d.). Dynamic-Link Library Security. Retrieved November 27, 2017.  url: https://msdn.microsoft.com/library/windows/desktop/ff919712.aspx     source_name: Microsoft Security Subsystem  description: Microsoft. (n.d.). Security Subsystem Architecture. Retrieved November 27, 2017.  url: https://technet.microsoft.com/library/cc961760.aspx     source_name: TechNet Autoruns  description: Russinovich, M. (2016, January 4). Autoruns for Windows v13.51. Retrieved June 6, 2016.  url: https://technet.microsoft.com/en-us/sysinternals/bb963902     