Encrypting Files with WinRar or 7zedit
Identifies use of WinRar or 7z to create an encrypted files. Adversaries will often compress and encrypt data in preparation for exfiltration.
Rule type: eql
Rule indices:
- logs-endpoint.events.*
- winlogbeat-*
- logs-windows.*
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:
- Elastic
- Host
- Windows
- Threat Detection
- Collection
Version: 4
Rule authors:
- Elastic
Rule license: Elastic License v2
Rule queryedit
process where event.type in ("start", "process_started") and ((process.name:"rar.exe" or process.code_signature.subject_name == "win.rar GmbH" or process.pe.original_file_name == "Command line RAR") and process.args == "a" and process.args : ("-hp*", "-p*", "-dw", "-tb", "-ta", "/hp*", "/p*", "/dw", "/tb", "/ta")) or (process.pe.original_file_name in ("7z.exe", "7za.exe") and process.args == "a" and process.args : ("-p*", "-sdel")) /* uncomment if noisy for backup software related FPs */ /* not process.parent.executable : ("C:\\Program Files\\*.exe", "C:\\Program Files (x86)\\*.exe") */
Framework: MITRE ATT&CKTM
-
Tactic:
- Name: Collection
- ID: TA0009
- Reference URL: https://attack.mitre.org/tactics/TA0009/
-
Technique:
- Name: Archive Collected Data
- ID: T1560
- Reference URL: https://attack.mitre.org/techniques/T1560/
-
Sub-technique:
- Name: Archive via Utility
- ID: T1560.001
- Reference URL: https://attack.mitre.org/techniques/T1560/001/