GAC DLL Loaded Via Office Applications

Title: GAC DLL Loaded Via Office Applications
Status: test
Description:Detects any GAC DLL being loaded by an Office Product
References:
  -https://medium.com/threatpunter/detecting-adversary-tradecraft-with-image-load-event-logging-and-eql-8de93338c16
Author: Antonlovesdnb
Date: 2020-02-19
modified:2023-02-10
Tags:

• -'attack.execution'
• -'attack.t1204.002'

Logsource:

• category: image_load
• product: windows

Detection:
  selection:
    Image|endswith:
      -'\excel.exe'
      -'\mspub.exe'
      -'\onenote.exe'
      -'\onenoteim.exe'
      -'\outlook.exe'
      -'\powerpnt.exe'
      -'\winword.exe'

    ImageLoaded|startswith: 'C:\Windows\Microsoft.NET\assembly\GAC_MSIL'
  condition:selection
Falsepositives:
  -Legitimate macro usage. Add the appropriate filter according to your environment
Level: high