Execution from Unusual Directory - Command Lineedit

Identifies process execution from suspicious default Windows directories. This may be abused by adversaries to hide malware in trusted paths.

Rule type: eql

Rule indices:

  • winlogbeat-*
  • logs-endpoint.events.*
  • logs-windows.*

Severity: medium

Risk score: 47

Runs every: 5 minutes

Searches indices from: now-9m (Date Math format, see also Additional look-back time)

Maximum alerts per execution: 100

Tags:

  • Elastic
  • Host
  • Windows
  • Threat Detection
  • Execution

Version: 5 (version history)

Added (Elastic Stack release): 7.11.0

Last modified (Elastic Stack release): 8.2.0

Rule authors: Elastic

Rule license: Elastic License v2

Investigation guideedit

## Triage and analysis

This is related to the `Process Execution from an Unusual Directory rule`.

## Config

If enabling an EQL rule on a non-elastic-agent index (such as beats) for versions <8.2, events will not define `event.ingested` and default fallback for EQL rules was not added until 8.2, so you will need to add a custom pipeline to populate `event.ingested` to @timestamp for this rule to work.

Rule queryedit

process where event.type in ("start", "process_started", "info") and
process.name : ("wscript.exe", "cscript.exe",
"rundll32.exe", "regsvr32.exe",
"cmstp.exe", "RegAsm.exe",
"installutil.exe", "mshta.exe",
"RegSvcs.exe", "powershell.exe",
"pwsh.exe", "cmd.exe") and /*
add suspicious execution paths here */ process.args :
("C:\\PerfLogs\\*", "C:\\Users\\Public\\*",
"C:\\Users\\Default\\*", "C:\\Windows\\Tasks\\*",
"C:\\Intel\\*", "C:\\AMD\\Temp\\*",
"C:\\Windows\\AppReadiness\\*",
"C:\\Windows\\ServiceState\\*",
"C:\\Windows\\security\\*",
"C:\\Windows\\IdentityCRL\\*",
"C:\\Windows\\Branding\\*", "C:\\Windows\\csc\\*",
"C:\\Windows\\DigitalLocker\\*", "C:\\Windows\\en-
US\\*", "C:\\Windows\\wlansvc\\*",
"C:\\Windows\\Prefetch\\*", "C:\\Windows\\Fonts\\*",
"C:\\Windows\\diagnostics\\*",
"C:\\Windows\\TAPI\\*", "C:\\Windows\\INF\\*",
"C:\\Windows\\System32\\Speech\\*",
"C:\\windows\\tracing\\*", "c:\\windows\\IME\\*",
"c:\\Windows\\Performance\\*",
"c:\\windows\\intel\\*", "c:\\windows\\ms\\*",
"C:\\Windows\\dot3svc\\*",
"C:\\Windows\\ServiceProfiles\\*",
"C:\\Windows\\panther\\*",
"C:\\Windows\\RemotePackages\\*",
"C:\\Windows\\OCR\\*", "C:\\Windows\\appcompat\\*",
"C:\\Windows\\apppatch\\*",
"C:\\Windows\\addins\\*", "C:\\Windows\\Setup\\*",
"C:\\Windows\\Help\\*", "C:\\Windows\\SKB\\*",
"C:\\Windows\\Vss\\*", "C:\\Windows\\Web\\*",
"C:\\Windows\\servicing\\*",
"C:\\Windows\\CbsTemp\\*", "C:\\Windows\\Logs\\*",
"C:\\Windows\\WaaS\\*", "C:\\Windows\\twain_32\\*",
"C:\\Windows\\ShellExperiences\\*",
"C:\\Windows\\ShellComponents\\*",
"C:\\Windows\\PLA\\*", "C:\\Windows\\Migration\\*",
"C:\\Windows\\debug\\*", "C:\\Windows\\Cursors\\*",
"C:\\Windows\\Containers\\*",
"C:\\Windows\\Boot\\*", "C:\\Windows\\bcastdvr\\*",
"C:\\Windows\\assembly\\*",
"C:\\Windows\\TextInput\\*",
"C:\\Windows\\security\\*",
"C:\\Windows\\schemas\\*",
"C:\\Windows\\SchCache\\*",
"C:\\Windows\\Resources\\*",
"C:\\Windows\\rescache\\*",
"C:\\Windows\\Provisioning\\*",
"C:\\Windows\\PrintDialog\\*",
"C:\\Windows\\PolicyDefinitions\\*",
"C:\\Windows\\media\\*",
"C:\\Windows\\Globalization\\*",
"C:\\Windows\\L2Schemas\\*",
"C:\\Windows\\LiveKernelReports\\*",
"C:\\Windows\\ModemLogs\\*",
"C:\\Windows\\ImmersiveControlPanel\\*",
"C:\\$Recycle.Bin\\*") and not process.parent.executable : ("C:\\WIN
DOWS\\System32\\DriverStore\\FileRepository\\*\\igfxCUIService*.exe",
"C:\\Windows\\System32\\spacedeskService.exe",
"C:\\Program Files\\Dell\\SupportAssistAgent\\SRE\\SRE.exe") and not
(process.name : "rundll32.exe" and process.args : ("uxtheme.dll,#64",
"PRINTUI.DLL,PrintUIEntry"))

Rule version historyedit

Version 5 (8.2.0 release)
  • Formatting only
Version 4 (7.13.0 release)
  • Updated query, changed from:

    process where event.type in ("start", "process_started", "info") and
    process.name : ("wscript.exe","cscript.exe","rundll32.exe","regsvr32.e
    xe","cmstp.exe","RegAsm.exe","installutil.exe","mshta.exe","RegSvcs.ex
    e", "powershell.exe", "pwsh.exe", "cmd.exe") and /* add suspicious
    execution paths here */ process.args : ("C:\\PerfLogs\\*","C:\\Users\\
    Public\\*","C:\\Users\\Default\\*","C:\\Windows\\Tasks\\*","C:\\Intel\
    \*", "C:\\AMD\\Temp\\*", "C:\\Windows\\AppReadiness\\*", "C:\\Window
    s\\ServiceState\\*","C:\\Windows\\security\\*","C:\\Windows\\IdentityC
    RL\\*","C:\\Windows\\Branding\\*","C:\\Windows\\csc\\*",
    "C:\\Windows\\DigitalLocker\\*","C:\\Windows\\en-US\\*","C:\\Windows\\
    wlansvc\\*","C:\\Windows\\Prefetch\\*","C:\\Windows\\Fonts\\*", "C:\\
    Windows\\diagnostics\\*","C:\\Windows\\TAPI\\*","C:\\Windows\\INF\\*",
    "C:\\Windows\\System32\\Speech\\*","C:\\windows\\tracing\\*", "c:\\wi
    ndows\\IME\\*","c:\\Windows\\Performance\\*","c:\\windows\\intel\\*","
    c:\\windows\\ms\\*","C:\\Windows\\dot3svc\\*","C:\\Windows\\ServicePro
    files\\*", "C:\\Windows\\panther\\*","C:\\Windows\\RemotePackages\\*"
    ,"C:\\Windows\\OCR\\*","C:\\Windows\\appcompat\\*","C:\\Windows\\apppa
    tch\\*","C:\\Windows\\addins\\*", "C:\\Windows\\Setup\\*","C:\\Window
    s\\Help\\*","C:\\Windows\\SKB\\*","C:\\Windows\\Vss\\*","C:\\Windows\\
    Web\\*","C:\\Windows\\servicing\\*","C:\\Windows\\CbsTemp\\*", "C:\\W
    indows\\Logs\\*","C:\\Windows\\WaaS\\*","C:\\Windows\\twain_32\\*","C:
    \\Windows\\ShellExperiences\\*","C:\\Windows\\ShellComponents\\*","C:\
    \Windows\\PLA\\*", "C:\\Windows\\Migration\\*","C:\\Windows\\debug\\*
    ","C:\\Windows\\Cursors\\*","C:\\Windows\\Containers\\*","C:\\Windows\
    \Boot\\*","C:\\Windows\\bcastdvr\\*", "C:\\Windows\\assembly\\*","C:\
    \Windows\\TextInput\\*","C:\\Windows\\security\\*","C:\\Windows\\schem
    as\\*","C:\\Windows\\SchCache\\*","C:\\Windows\\Resources\\*", "C:\\W
    indows\\rescache\\*","C:\\Windows\\Provisioning\\*","C:\\Windows\\Prin
    tDialog\\*","C:\\Windows\\PolicyDefinitions\\*","C:\\Windows\\media\\*
    ", "C:\\Windows\\Globalization\\*","C:\\Windows\\L2Schemas\\*","C:\\W
    indows\\LiveKernelReports\\*","C:\\Windows\\ModemLogs\\*","C:\\Windows
    \\ImmersiveControlPanel\\*", "C:\\$Recycle.Bin\\*")
Version 3 (7.12.0 release)
  • Updated query, changed from:

    process where event.type in ("start", "process_started", "info") and
    process.name : ("wscript.exe","cscript.exe","rundll32.exe","regsvr32.e
    xe","cmstp.exe","RegAsm.exe","installutil.exe","mshta.exe","RegSvcs.ex
    e") and /* add suspicious execution paths here */ process.args : ("C:
    \\PerfLogs\\*","C:\\Users\\Public\\*","C:\\Users\\Default\\*","C:\\Win
    dows\\Tasks\\*","C:\\Intel\\*", "C:\\AMD\\Temp\\*",
    "C:\\Windows\\AppReadiness\\*", "C:\\Windows\\ServiceState\\*","C:\\Wi
    ndows\\security\\*","C:\\Windows\\IdentityCRL\\*","C:\\Windows\\Brandi
    ng\\*","C:\\Windows\\csc\\*",
    "C:\\Windows\\DigitalLocker\\*","C:\\Windows\\en-US\\*","C:\\Windows\\
    wlansvc\\*","C:\\Windows\\Prefetch\\*","C:\\Windows\\Fonts\\*", "C:\\
    Windows\\diagnostics\\*","C:\\Windows\\TAPI\\*","C:\\Windows\\INF\\*",
    "C:\\Windows\\System32\\Speech\\*","C:\\windows\\tracing\\*", "c:\\wi
    ndows\\IME\\*","c:\\Windows\\Performance\\*","c:\\windows\\intel\\*","
    c:\\windows\\ms\\*","C:\\Windows\\dot3svc\\*","C:\\Windows\\ServicePro
    files\\*", "C:\\Windows\\panther\\*","C:\\Windows\\RemotePackages\\*"
    ,"C:\\Windows\\OCR\\*","C:\\Windows\\appcompat\\*","C:\\Windows\\apppa
    tch\\*","C:\\Windows\\addins\\*", "C:\\Windows\\Setup\\*","C:\\Window
    s\\Help\\*","C:\\Windows\\SKB\\*","C:\\Windows\\Vss\\*","C:\\Windows\\
    Web\\*","C:\\Windows\\servicing\\*","C:\\Windows\\CbsTemp\\*", "C:\\W
    indows\\Logs\\*","C:\\Windows\\WaaS\\*","C:\\Windows\\twain_32\\*","C:
    \\Windows\\ShellExperiences\\*","C:\\Windows\\ShellComponents\\*","C:\
    \Windows\\PLA\\*", "C:\\Windows\\Migration\\*","C:\\Windows\\debug\\*
    ","C:\\Windows\\Cursors\\*","C:\\Windows\\Containers\\*","C:\\Windows\
    \Boot\\*","C:\\Windows\\bcastdvr\\*", "C:\\Windows\\assembly\\*","C:\
    \Windows\\TextInput\\*","C:\\Windows\\security\\*","C:\\Windows\\schem
    as\\*","C:\\Windows\\SchCache\\*","C:\\Windows\\Resources\\*", "C:\\W
    indows\\rescache\\*","C:\\Windows\\Provisioning\\*","C:\\Windows\\Prin
    tDialog\\*","C:\\Windows\\PolicyDefinitions\\*","C:\\Windows\\media\\*
    ", "C:\\Windows\\Globalization\\*","C:\\Windows\\L2Schemas\\*","C:\\W
    indows\\LiveKernelReports\\*","C:\\Windows\\ModemLogs\\*","C:\\Windows
    \\ImmersiveControlPanel\\*")
Version 2 (7.11.2 release)
  • Formatting only