Query: SIEM correlation: stealth activity consistent with Access Token Manipulation
Matching passage: T1134 Access Token Manipulation. Tactics: stealth, privilege escalation. Description: Adversaries may modify access tokens to operate under a different user or system security context to perform actions and bypass access controls. Windows uses access tokens to determine the ownership of a running process. A user can manipulate access tokens to make a running process appear as though it is the child of a different process or belongs to someone other than the user that started the process. When this occurs, the process also takes on the security context associated with the new token. An adversary can use built-in Windows API functions to copy access tokens from existing processes; this is known as token stealing. These token can then be applied to an existing process (i.e. [Token Impersonation/Theft](https://attack.mitre.org/techniques/T1134/001)) or used to spawn a new process (i.e. [Create Process with Token](https://attack.mitre.org/techniques/T1134/002)). An adversary must already be in a privileged user context (i.e. administrator) to steal a token. However, adversaries commonly use token stealing to elevate their security context from the administrator level to the SYSTEM level. An adversary can then use a token to authenticate to a remote system as the account for that token if the account has appropriate permissions on the remote system.(Citation: Pentestlab Token Manipulation) Any standard user can use the <code>runas</code> command, and the Windows API functions, to create impersonation tokens; it does not require access to an administrator account. There are also other mechanisms, such as Active Directory fields, that can be used to modify access tokens.
Near-miss passage: T1134.004 Parent PID Spoofing. Tactics: stealth, privilege escalation. Description: Adversaries may spoof the parent process identifier (PPID) of a new process to evade process-monitoring defenses or to elevate privileges. New processes are typically spawned directly from their parent, or calling, process unless explicitly specified. One way of explicitly assigning the PPID of a new process is via the <code>CreateProcess</code> API call, which supports a parameter that defines the PPID to use.(Citation: DidierStevens SelectMyParent Nov 2009) This functionality is used by Windows features such as User Account Control (UAC) to correctly set the PPID after a requested elevated process is spawned by SYSTEM (typically via <code>svchost.exe</code> or <code>consent.exe</code>) rather than the current user context.(Citation: Microsoft UAC Nov 2018) Adversaries may abuse these mechanisms to evade defenses, such as those blocking processes spawning directly from Office documents, and analysis targeting unusual/potentially malicious parent-child process relationships, such as spoofing the PPID of [PowerShell](https://attack.mitre.org/techniques/T1059/001)/[Rundll32](https://attack.mitre.org/techniques/T1218/011) to be <code>explorer.exe</code> rather than an Office document delivered as part of [Spearphishing Attachment](https://attack.mitre.org/techniques/T1566/001).(Citation: CounterCept PPID Spoofing Dec 2018) This spoofing could be executed via [Visual Basic](https://attack.mitre.org/techniques/T1059/005) within a malicious Office document or any code that can perform [Native API](https://attack.mitre.org/techniques/T1106).(Citation: CTD PPID Spoofing Macro Mar 2019)(Citation: CounterCept PPID Spoofing Dec 2018) Explicitly assigning the PPID may also enable elevated privileges given appropriate access rights to the parent process. For example, an adversary in a privileged user context (i.e. administrator) may spawn a new process and assign the parent as a process running as SYSTEM (such as <code>lsass.exe</code>), causing the new process to be elevated vi