IMPORTANT: No additional bug fixes or documentation updates
will be released for this version. For the latest information, see the
current release documentation.
System Shells via Services
editSystem Shells via Services
editWindows services typically run as SYSTEM and can be used as a privilege escalation opportunity. Malware or penetration testers may run a shell as a service to gain SYSTEM permissions.
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
- Persistence
Version: 11 (version history)
Added (Elastic Stack release): 7.6.0
Last modified (Elastic Stack release): 8.2.0
Rule authors: Elastic
Rule license: Elastic License v2
Investigation guide
edit## Triage and analysis ### Investigating System Shells via Services Attackers may configure existing services or create new ones to execute system shells to elevate their privileges from administrator to SYSTEM. They can also configure services to execute these shells with persistence payloads. This rule looks for system shells being spawned by `services.exe`, which is compatible with the above behavior. #### Possible investigation steps - Investigate the process execution chain (parent process tree). - Identify how the service was created or modified. Look for registry changes events or Windows events related to service activities (for example, 4697 and/or 7045). - Identify the user account that performed the action and whether it should perform this kind of action. - Contact the account owner and confirm whether they are aware of this activity. - Investigate other alerts associated with the user/host during the past 48 hours. - Check for similar behavior in other hosts on the environment. - Check for commands executed under the spawned shell. ### False positive analysis - This activity should not happen legitimately. The security team should address any potential benign true positive (B-TP), as this configuration can put the user and the domain at risk. ### Response and remediation - Initiate the incident response process based on the outcome of the triage. - Isolate the involved host to prevent further post-compromise behavior. - Reset passwords for the user account and other potentially compromised accounts (email, services, CRMs, etc.). - Delete the service or restore it to the original configuration. - Investigate the initial attack vector. ## 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 query
editprocess where event.type in ("start", "process_started") and process.parent.name : "services.exe" and process.name : ("cmd.exe", "powershell.exe", "pwsh.exe", "powershell_ise.exe") and /* Third party FP's */ not process.args : "NVDisplay.ContainerLocalSystem"
Threat mapping
editFramework: MITRE ATT&CKTM
-
Tactic:
- Name: Persistence
- ID: TA0003
- Reference URL: https://attack.mitre.org/tactics/TA0003/
-
Technique:
- Name: Create or Modify System Process
- ID: T1543
- Reference URL: https://attack.mitre.org/techniques/T1543/
Rule version history
edit- Version 11 (8.2.0 release)
-
- Formatting only
- Version 10 (7.16.0 release)
-
-
Updated query, changed from:
process where event.type in ("start", "process_started") and process.parent.name : "services.exe" and process.name : ("cmd.exe", "powershell.exe") and /* Third party FP's */ not process.args : "NVDisplay.ContainerLocalSystem"
-
- Version 9 (7.13.0 release)
-
-
Updated query, changed from:
event.category:process and event.type:(start or process_started) and process.parent.name:services.exe and process.name:(cmd.exe or powershell.exe)
-
- Version 8 (7.12.0 release)
-
- Formatting only
- Version 7 (7.11.2 release)
-
- Formatting only
- Version 6 (7.11.0 release)
-
- Formatting only
- Version 5 (7.10.0 release)
-
- Formatting only
- Version 4 (7.9.1 release)
-
- Formatting only
- Version 3 (7.9.0 release)
-
-
Updated query, changed from:
event.action:"Process Create (rule: ProcessCreate)" and process.parent.name:services.exe and process.name:(cmd.exe or powershell.exe)
-
- Version 2 (7.7.0 release)
-
-
Updated query, changed from:
event.action:"Process Create (rule: ProcessCreate)" and process.parent.name:"services.exe" and process.name:("cmd.exe" or "powershell.exe")
-