WinRAR Execution in Non-Standard Folder

Hunt Hypothesis

Detects a suspicious WinRAR execution in a folder which is not the default installation folder

Detection Rule

Sigma (Original)

title: WinRAR Execution in Non-Standard Folder
id: 4ede543c-e098-43d9-a28f-dd784a13132f
status: test
description: Detects a suspicious WinRAR execution in a folder which is not the default installation folder
references:
    - https://twitter.com/cyb3rops/status/1460978167628406785
author: Florian Roth (Nextron Systems), Tigzy
date: 2021-11-17
modified: 2025-07-16
tags:
    - attack.collection
    - attack.t1560.001
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        - Image|endswith:
              - '\rar.exe'
              - '\winrar.exe'
        - Description:
              - 'Command line RAR'
              - 'WinRAR'
    filter_main_unrar:
        # Note: we filter unrar as it has the same description as the other utilities, and we're only interested in compression
        Image|endswith: '\UnRAR.exe'
    filter_main_path:
        Image|contains:
            - ':\Program Files (x86)\WinRAR\'
            - ':\Program Files\WinRAR\'
    filter_optional_temp:
        # Note: in some occasion installers were seen dropping "rar" in TEMP
        Image|contains: ':\Windows\Temp\'
    condition: selection and not 1 of filter_main_* and not 1 of filter_optional_*
falsepositives:
    - Legitimate use of WinRAR in a folder of a software that bundles WinRAR
level: medium

KQL (Azure Sentinel)

imProcessCreate
| where ((TargetProcessName endswith "\\rar.exe" or TargetProcessName endswith "\\winrar.exe") or (TargetProcessFileDescription in~ ("Command line RAR", "WinRAR"))) and (not((TargetProcessName endswith "\\UnRAR.exe" or (TargetProcessName contains ":\\Program Files (x86)\\WinRAR\\" or TargetProcessName contains ":\\Program Files\\WinRAR\\")))) and (not(TargetProcessName contains ":\\Windows\\Temp\\"))

Required Data Sources

False Positive Guidance

• Legitimate use of WinRAR in a folder of a software that bundles WinRAR

MITRE ATT&CK Context

• Tactic: Collection
• Technique: T1560.001 — T1560.001

References

• https://twitter.com/cyb3rops/status/1460978167628406785
• SigmaHQ Rule