Microsoft Exchange Worker Spawning Suspicious Processesedit
Identifies suspicious processes being spawned by the Microsoft Exchange Server worker process (w3wp). This activity may indicate exploitation activity or access to an existing web shell backdoor.
Rule type: eql
Rule indices:
- logs-endpoint.events.*
- winlogbeat-*
- logs-windows.*
Severity: high
Risk score: 73
Runs every: 5 minutes
Searches indices from: now-9m (Date Math format, see also Additional look-back time)
Maximum alerts per execution: 100
References:
Tags:
- Elastic
- Host
- Windows
- Threat Detection
- Initial Access
Version: 100 (version history)
Added (Elastic Stack release): 7.12.0
Last modified (Elastic Stack release): 8.5.0
Rule authors: Elastic
Rule license: Elastic License v2
Investigation guideedit
Rule queryedit
process where event.type == "start" and process.parent.name :
"w3wp.exe" and process.parent.args : "MSExchange*AppPool" and
(process.name : ("cmd.exe", "powershell.exe", "pwsh.exe",
"powershell_ise.exe") or process.pe.original_file_name in
("cmd.exe", "powershell.exe", "pwsh.dll", "powershell_ise.exe"))
Threat mappingedit
Framework: MITRE ATT&CKTM
-
Tactic:
- Name: Initial Access
- ID: TA0001
- Reference URL: https://attack.mitre.org/tactics/TA0001/
-
Technique:
- Name: Exploit Public-Facing Application
- ID: T1190
- Reference URL: https://attack.mitre.org/techniques/T1190/
Rule version historyedit
- Version 100 (8.5.0 release)
-
- Formatting only
- Version 5 (8.4.0 release)
-
- Formatting only
- Version 3 (8.2.0 release)
-
- Formatting only
- Version 2 (7.16.0 release)
-
-
Updated query, changed from:
process where event.type == "start" and process.parent.name : "w3wp.exe" and process.parent.args : "MSExchange*AppPool" and (process.name : ("cmd.exe", "powershell.exe", "pwsh.exe") or process.pe.original_file_name : ("cmd.exe", "powershell.exe", "pwsh.exe"))
-