Suspicious Desktopimgdownldr Target File

Title: Suspicious Desktopimgdownldr Target File
Status: test
Description:Detects a suspicious Microsoft desktopimgdownldr file creation that stores a file to a suspicious location or contains a file with a suspicious extension
References:
  -https://labs.sentinelone.com/living-off-windows-land-a-new-native-file-downldr/
  -https://twitter.com/SBousseaden/status/1278977301745741825
Author: Florian Roth (Nextron Systems)
Date: 2020-07-03
modified:2022-06-02
Tags:

• -'attack.command-and-control'
• -'attack.t1105'

Logsource:

• product: windows
• category: file_event

Detection:
  selection:
    Image|endswith: '\svchost.exe'
    TargetFilename|contains: '\Personalization\LockScreenImage\'
  filter1:
    TargetFilename|contains: 'C:\Windows\'
  filter2:
    TargetFilename|contains:
      -'.jpg'
      -'.jpeg'
      -'.png'

  condition:selection and not filter1 and not filter2
Falsepositives:
  -False positives depend on scripts and administrative tools used in the monitored environment
Level: high