ISO or Image Mount Indicator in Recent Files

Title: ISO or Image Mount Indicator in Recent Files
Status: test
Description:Detects the creation of recent element file that points to an .ISO, .IMG, .VHD or .VHDX file as often used in phishing attacks. This can be a false positive on server systems but on workstations users should rarely mount .iso or .img files.
References:
  -https://www.microsoft.com/security/blog/2021/05/27/new-sophisticated-email-based-attack-from-nobelium/
  -https://www.trendmicro.com/vinfo/us/security/news/cybercrime-and-digital-threats/malicious-spam-campaign-uses-iso-image-files-to-deliver-lokibot-and-nanocore
  -https://blog.emsisoft.com/en/32373/beware-new-wave-of-malware-spreads-via-iso-file-email-attachments/
  -https://insights.sei.cmu.edu/blog/the-dangers-of-vhd-and-vhdx-files/
Author: Florian Roth (Nextron Systems)
Date: 2022-02-11
modified:None
Tags:

• -'attack.initial-access'
• -'attack.t1566.001'

Logsource:

• product: windows
• category: file_event

Detection:
  selection:
    TargetFilename|endswith:
      -'.iso.lnk'
      -'.img.lnk'
      -'.vhd.lnk'
      -'.vhdx.lnk'

    TargetFilename|contains: '\Microsoft\Windows\Recent\'
  condition:selection
Falsepositives:
  -Cases in which a user mounts an image file for legitimate reasons
Level: medium