Suspicious File Execution From Internet Hosted WebDav Share — Sigma Rule

Rule metadata and linked tags

Author: pH-T (Nextron Systems). Source status: test; severity: high. Source dates: 2022-09-01 / 2023-02-21.

{
  "category": "process_creation",
  "product": "windows"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: f13bed6d00409c8104bfebe2934f48f9bcd9557a802e7c6bcfd1f3c2f5cfdb2d

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: Suspicious File Execution From Internet Hosted WebDav Share
id: f0507c0f-a3a2-40f5-acc6-7f543c334993
status: test
description: Detects the execution of the "net use" command to mount a WebDAV server and then immediately execute some content in it. As seen being used in malicious LNK files
references:
    - https://twitter.com/ShadowChasing1/status/1552595370961944576
    - https://www.virustotal.com/gui/file/a63376ee1dba76361df73338928e528ca5b20171ea74c24581605366dcaa0104/behavior
author: pH-T (Nextron Systems)
date: 2022-09-01
modified: 2023-02-21
tags:
    - attack.execution
    - attack.t1059.001
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - Image|contains: '\cmd.exe'
        - OriginalFileName: 'Cmd.EXE'
    selection_base:
        CommandLine|contains|all:
            - ' net use http'
            - '& start /b '
            - '\DavWWWRoot\'
    selection_ext:
        CommandLine|contains:
            - '.exe '
            - '.dll '
            - '.bat '
            - '.vbs '
            - '.ps1 '
    condition: all of selection_*
falsepositives:
    - Unknown
level: high

Original YAML and metadata in JSON

False positives

• Unknown

Source references

• https://twitter.com/ShadowChasing1/status/1552595370961944576
• https://www.virustotal.com/gui/file/a63376ee1dba76361df73338928e528ca5b20171ea74c24581605366dcaa0104/behavior