sigmahighHunting

.RDP File Created By Uncommon Application

Detects creation of a file with an ".rdp" extension by an application that doesn't commonly create such files.

Detection Query

selection:
  TargetFilename|endswith: .rdp
  Image|endswith:
    - \brave.exe
    - \CCleaner Browser\Application\CCleanerBrowser.exe
    - \chromium.exe
    - \firefox.exe
    - \Google\Chrome\Application\chrome.exe
    - \iexplore.exe
    - \microsoftedge.exe
    - \msedge.exe
    - \Opera.exe
    - \Vivaldi.exe
    - \Whale.exe
    - \olk.exe
    - \Outlook.exe
    - \RuntimeBroker.exe
    - \Thunderbird.exe
    - \Discord.exe
    - \Keybase.exe
    - \msteams.exe
    - \Slack.exe
    - \teams.exe
condition: selection

Author

Nasreddine Bencherchali (Nextron Systems)

Created

2023-04-18

Data Sources

windowsFile Events

Platforms

windows

References

Tags

attack.defense-evasion

Raw Content

title: .RDP File Created By Uncommon Application
id: fccfb43e-09a7-4bd2-8b37-a5a7df33386d
related:
    - id: f748c45a-f8d3-4e6f-b617-fe176f695b8f
      type: derived
status: test
description: |
    Detects creation of a file with an ".rdp" extension by an application that doesn't commonly create such files.
references:
    - https://www.blackhillsinfosec.com/rogue-rdp-revisiting-initial-access-methods/
    - https://web.archive.org/web/20230726144748/https://blog.thickmints.dev/mintsights/detecting-rogue-rdp/
author: Nasreddine Bencherchali (Nextron Systems)
date: 2023-04-18
modified: 2024-11-01
tags:
    - attack.defense-evasion
logsource:
    product: windows
    category: file_event
detection:
    selection:
        TargetFilename|endswith: '.rdp'
        Image|endswith:
            # Covers browsers
            - '\brave.exe'
            - '\CCleaner Browser\Application\CCleanerBrowser.exe'
            - '\chromium.exe'
            - '\firefox.exe'
            - '\Google\Chrome\Application\chrome.exe'
            - '\iexplore.exe'
            - '\microsoftedge.exe'
            - '\msedge.exe'
            - '\Opera.exe'
            - '\Vivaldi.exe'
            - '\Whale.exe'
            # Covers email clients
            - '\olk.exe' # Outlook
            - '\Outlook.exe'
            - '\RuntimeBroker.exe' # If the windows mail client is used
            - '\Thunderbird.exe'
            # Covers chat applications
            - '\Discord.exe' # Should open the browser for download, but just in case.
            - '\Keybase.exe'
            - '\msteams.exe'
            - '\Slack.exe'
            - '\teams.exe'
    condition: selection
falsepositives:
    - Unknown
level: high