Windows Network Access Suspicious desktop.ini Action — Sigma Rule

Rule metadata and linked tags

Author: Tim Shelton (HAWK.IO). Source status: test; severity: medium. Source dates: 2021-12-06 / 2022-01-16.

{
  "product": "windows",
  "service": "security"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: a9159e5cc19376051d394150d9c0e93a2e6cb7bf6aaa086a995d62d7ef3c7b15

Detection logic

Original source YAML. Source-tag agreement is not proof of complete semantic coverage. This rule has not been compiled for a SIEM backend or validated against live telemetry here.

title: Windows Network Access Suspicious desktop.ini Action
id: 35bc7e28-ee6b-492f-ab04-da58fcf6402e
status: test
description: Detects unusual processes accessing desktop.ini remotely over network share, which can be leveraged to alter how Explorer displays a folder's content (i.e. renaming files) without changing them on disk.
references:
    - https://isc.sans.edu/forums/diary/Desktopini+as+a+postexploitation+tool/25912/
author: Tim Shelton (HAWK.IO)
date: 2021-12-06
modified: 2022-01-16
tags:
    - attack.privilege-escalation
    - attack.persistence
    - attack.t1547.009
logsource:
    product: windows
    service: security
detection:
    selection:
        EventID: 5145
        ObjectType: File
        RelativeTargetName|endswith: '\desktop.ini'
        AccessList|contains:
            - 'WriteData'
            - 'DELETE'
            - 'WriteDAC'
            - 'AppendData'
            - 'AddSubdirectory'
    condition: selection
falsepositives:
    - Read only access list authority
level: medium

Original YAML and metadata in JSON

False positives

• Read only access list authority

Source references

• https://isc.sans.edu/forums/diary/Desktopini+as+a+postexploitation+tool/25912/