Unusual Print Spooler Child Process
editUnusual Print Spooler Child Process
editDetects unusual Print Spooler service (spoolsv.exe) child processes. This may indicate an attempt to exploit privilege escalation vulnerabilities related to the Printing Service on Windows.
Rule type: eql
Rule indices:
- winlogbeat-*
- logs-endpoint.events.*
- logs-windows.*
- logs-system.security*
Severity: medium
Risk score: 47
Runs every: 5m
Searches indices from: now-9m (Date Math format, see also Additional look-back time
)
Maximum alerts per execution: 100
References:
Tags:
- Domain: Endpoint
- OS: Windows
- Use Case: Threat Detection
- Tactic: Privilege Escalation
- Use Case: Vulnerability
- Data Source: Elastic Defend
Version: 107
Rule authors:
- Elastic
Rule license: Elastic License v2
Setup
editSetup
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 version 8.2.
Hence for this rule to work effectively, users will need to add a custom ingest pipeline to populate
event.ingested
to @timestamp.
For more details on adding a custom ingest pipeline refer - https://www.elastic.co/guide/en/fleet/current/data-streams-pipeline-tutorial.html
Rule query
editprocess where host.os.type == "windows" and event.type == "start" and process.parent.name : "spoolsv.exe" and process.command_line != null and (?process.Ext.token.integrity_level_name : "System" or ?winlog.event_data.IntegrityLevel : "System") and /* exclusions for FP control below */ not process.name : ("splwow64.exe", "PDFCreator.exe", "acrodist.exe", "spoolsv.exe", "msiexec.exe", "route.exe", "WerFault.exe") and not process.command_line : "*\\WINDOWS\\system32\\spool\\DRIVERS*" and not (process.name : "net.exe" and process.command_line : ("*stop*", "*start*")) and not (process.name : ("cmd.exe", "powershell.exe") and process.command_line : ("*.spl*", "*\\program files*", "*route add*")) and not (process.name : "netsh.exe" and process.command_line : ("*add portopening*", "*rule name*")) and not (process.name : "regsvr32.exe" and process.command_line : "*PrintConfig.dll*") and not process.executable : ( "?:\\Program Files (x86)\\CutePDF Writer\\CPWriter2.exe", "?:\\Program Files (x86)\\GPLGS\\gswin32c.exe" )
Framework: MITRE ATT&CKTM
-
Tactic:
- Name: Privilege Escalation
- ID: TA0004
- Reference URL: https://attack.mitre.org/tactics/TA0004/
-
Technique:
- Name: Exploitation for Privilege Escalation
- ID: T1068
- Reference URL: https://attack.mitre.org/techniques/T1068/