Query: Encoded PowerShell / command-line abuse matching At
Matching passage: T1053.002 At. Tactics: execution, persistence, privilege escalation. Description: Adversaries may abuse the [at](https://attack.mitre.org/software/S0110) utility to perform task scheduling for initial or recurring execution of malicious code. The [at](https://attack.mitre.org/software/S0110) utility exists as an executable within Windows, Linux, and macOS for scheduling tasks at a specified time and date. Although deprecated in favor of [Scheduled Task](https://attack.mitre.org/techniques/T1053/005)'s [schtasks](https://attack.mitre.org/software/S0111) in Windows environments, using [at](https://attack.mitre.org/software/S0110) requires that the Task Scheduler service be running, and the user to be logged on as a member of the local Administrators group. In addition to explicitly running the `at` command, adversaries may also schedule a task with [at](https://attack.mitre.org/software/S0110) by directly leveraging the [Windows Management Instrumentation](https://attack.mitre.org/techniques/T1047) `Win32_ScheduledJob` WMI class.(Citation: Malicious Life by Cybereason) On Linux and macOS, [at](https://attack.mitre.org/software/S0110) may be invoked by the superuser as well as any users added to the <code>at.allow</code> file. If the <code>at.allow</code> file does not exist, the <code>at.deny</code> file is checked. Every username not listed in <code>at.deny</code> is allowed to invoke [at](https://attack.mitre.org/software/S0110). If the <code>at.deny</code> exists and is empty, global use of [at](https://attack.mitre.org/software/S0110) is permitted. If neither file exists (which is often the baseline) only the superuser is allowed to use [at](https://attack.mitre.org/software/S0110).(Citation: Linux at) Adversaries may use [at](https://attack.mitre.org/software/S0110) to execute programs at system startup or on a scheduled basis for [Persistence](https://attack.mitre.org/tactics/TA0003). [at](https://attack.mitre.org/software/S0110) can also be abused to conduct remote [Execution](https://attack.mitre.org/tactics/TA0002) as part of [Lateral Move
Near-miss passage: T1053 Scheduled Task/Job. Tactics: execution, persistence, privilege escalation. Description: Adversaries may abuse task scheduling functionality to facilitate initial or recurring execution of malicious code. Utilities exist within all major operating systems to schedule programs or scripts to be executed at a specified date and time. A task can also be scheduled on a remote system, provided the proper authentication is met (ex: RPC and file and printer sharing in Windows environments). Scheduling a task on a remote system typically may require being a member of an admin or otherwise privileged group on the remote system.(Citation: TechNet Task Scheduler Security) Adversaries may use task scheduling to execute programs at system startup or on a scheduled basis for persistence. These mechanisms can also be abused to run a process under the context of a specified account (such as one with elevated permissions/privileges). Similar to [System Binary Proxy Execution](https://attack.mitre.org/techniques/T1218), adversaries have also abused task scheduling to potentially mask one-time execution under a trusted system process.(Citation: ProofPoint Serpent)