Virtualization/Sandbox Evasion: Time Based Evasion

Adversaries may employ various time-based methods to detect and avoid virtualization and analysis environments. This may include enumerating time-based properties, such as uptime or the system clock, as well as the use of timers or other triggers to avoid a virtual machine environment (VME) or sandbox, specifically those that are automated or only operate for a limited amount of time.

Adversaries may employ various time-based evasions, such as delaying malware functionality upon initial execution using programmatic sleep commands or native system scheduling functionality (ex: Scheduled Task/Job). Delays may also be based on waiting for specific victim conditions to be met (ex: system time, events, etc.) or employ scheduled Multi-Stage Channels to avoid analysis and scrutiny.[1]

Benign commands or other operations may also be used to delay malware execution. Loops or otherwise needless repetitions of commands, such as Pings, may be used to delay malware execution and potentially exceed time thresholds of automated analysis environments.[2][3] Another variation, commonly referred to as API hammering, involves making various calls to Native API functions in order to delay execution (while also potentially overloading analysis environments with junk data).[4][5]

Adversaries may also use time as a metric to detect sandboxes and analysis environments, particularly those that attempt to manipulate time mechanisms to simulate longer elapses of time. For example, an adversary may be able to identify a sandbox accelerating time by sampling and calculating the expected value for an environment's timestamp before and after execution of a sleep function.[6]

ID: T1497.003
Sub-technique of:  T1497
Platforms: Linux, Windows, macOS
Defense Bypassed: Anti-virus, Host forensic analysis, Signature-based detection, Static File Analysis
Contributors: Deloitte Threat Library Team; Jeff Felling, Red Canary; Jorge Orchilles, SCYTHE; Ruben Dodge, @shotgunner101
Version: 1.2
Created: 06 March 2020
Last Modified: 15 October 2021

Procedure Examples

ID Name Description
S0584 AppleJeus

AppleJeus has waited a specified time before downloading a second stage payload.[7]


BADFLICK has delayed communication to the actor-controlled IP address by 5 minutes.[8]

S0534 Bazar

Bazar can use a timer to delay execution of core functionality.[9]

S0574 BendyBear

BendyBear can check for analysis environments and signs of debugging using the Windows API kernel32!GetTickCountKernel32 call.[10]

S0268 Bisonal

Bisonal has checked if the malware is running in a virtual environment with the anti-debug function GetTickCount() to compare the timing.[11][12]

S1063 Brute Ratel C4

Brute Ratel C4 can call NtDelayExecution to pause execution.[13][14]

S1039 Bumblebee

Bumblebee has the ability to set a hardcoded and randomized sleep interval.[15]

S0660 Clambling

Clambling can wait 30 minutes before initiating contact with C2.[16]

S0611 Clop

Clop has used the sleep command to avoid sandbox detection.[17]

S0115 Crimson

Crimson can determine when it has been installed on a host for at least 15 days before downloading the final payload.[18]

S1066 DarkTortilla

DarkTortilla can implement the kernel32.dll Sleep function to delay execution for up to 300 seconds before implementing persistence or processing an addon package.[19]

S0694 DRATzarus

DRATzarus can use the GetTickCount and GetSystemTimeAsFileTime API calls to measure function timing.[20] DRATzarus can also remotely shut down into sleep mode under specific conditions to evade detection.[20]

S0554 Egregor

Egregor can perform a long sleep (greater than or equal to 3 minutes) to evade detection.[21]

S0396 EvilBunny

EvilBunny has used time measurements from 3 different APIs before and after performing sleep operations to check and abort if the malware is running in a sandbox.[22]

S0512 FatDuke

FatDuke can turn itself on or off at random intervals.[23]

S0493 GoldenSpy

GoldenSpy's installer has delayed installation of GoldenSpy for two hours after it reaches a victim system.[24]

S0588 GoldMax

GoldMax has set an execution trigger date and time, stored as an ASCII Unix/Epoch time value.[25]

S0632 GrimAgent

GrimAgent can sleep for 195 - 205 seconds after payload execution and before deleting its task.[26]

S0561 GuLoader

GuLoader has the ability to perform anti-debugging based on time checks, API calls, and CPUID.[27]

S0697 HermeticWiper

HermeticWiper has the ability to receive a command parameter to sleep prior to carrying out destructive actions on a targeted host.[28]

S0513 LiteDuke

LiteDuke can wait 30 seconds before executing additional code if security software is detected.[23]

S0447 Lokibot

Lokibot has performed a time-based anti-debug check before downloading its third stage.[29]

S1059 metaMain

metaMain has delayed execution for five to six minutes during its persistence establishment process.[30]

S0439 Okrum

Okrum's loader can detect presence of an emulator by using two calls to GetTickCount API, and checking whether the time has been accelerated.[31]

C0022 Operation Dream Job

During Operation Dream Job, Lazarus Group used tools that collected GetTickCount and GetSystemTimeAsFileTime data to detect sandbox or VMware services.[20]

S0626 P8RAT

P8RAT has the ability to "sleep" for a specified time to evade detection.[32]

S0453 Pony

Pony has delayed execution using a built-in function to avoid detection and analysis.[33]

S0650 QakBot

The QakBot dropper can delay dropping the payload to evade detection.[34][35]

S0565 Raindrop

After initial installation, Raindrop runs a computation to delay execution.[36]

S1018 Saint Bot

Saint Bot has used the command timeout 20 to pause the execution of its initial loader.[37]

S1086 Snip3

Snip3 can execute WScript.Sleep to delay execution of its second stage.[38]

S0627 SodaMaster

SodaMaster has the ability to put itself to "sleep" for a specified time.[32]

S1034 StrifeWater

StrifeWater can modify its sleep time responses from the default of 20-22 seconds.[39]


SUNBURST remained dormant after initial access for a period of up to two weeks.[40]

S1064 SVCReady

SVCReady can enter a sleep stage for 30 minutes to evade detection.[41]

S0595 ThiefQuest

ThiefQuest invokes time call to check the system's time, executes a sleep command, invokes a second time call, and then compares the time difference between the two time calls and the amount of time the system slept to identify the sandbox.[42]

S0671 Tomiris

Tomiris has the ability to sleep for at least nine minutes to evade sandbox-based analysis systems.[43]

S0266 TrickBot

TrickBot has used printf and file I/O loops to delay process execution as part of API hammering.[5]

S0386 Ursnif

Ursnif has used a 30 minute delay after execution to evade sandbox monitoring tools.[44]

S0689 WhisperGate

WhisperGate can pause for 20 seconds to bypass antivirus solutions.[45][46]


Using the machine's local time, XCSSET waits 43200 seconds (12 hours) from the initial creation timestamp of a specific file, .report. After the elapsed time, XCSSET executes additional modules.[47]


This type of attack technique cannot be easily mitigated with preventive controls since it is based on the abuse of system features.


ID Data Source Data Component Detects
DS0017 Command Command Execution

Monitor executed commands and arguments that may employ various time-based methods to detect and avoid virtualization and analysis environments. Detecting actions related to virtualization and sandbox identification may be difficult depending on the adversary's implementation and monitoring required.

DS0009 Process OS API Execution

Monitor for API calls that may employ various time-based methods to detect and avoid virtualization and analysis environments. Detecting actions related to virtualization and sandbox identification may be difficult depending on the adversary's implementation and monitoring required.

Process Creation

Time-based evasion will likely occur in the first steps of an operation but may also occur throughout as an adversary learns the environment. Data and events should not be viewed in isolation, but as part of a chain of behavior that could lead to other activities, such as lateral movement, based on the information obtained. Detecting actions related to virtualization and sandbox identification may be difficult depending on the adversary's implementation and monitoring required. Monitoring for suspicious processes being spawned that gather a variety of system information or perform other forms of Discovery, especially in a short period of time, may aid in detection.


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