Add Potential Suspicious New Download Source To Winget — Sigma Rule

Rule metadata and linked tags

Author: Nasreddine Bencherchali (Nextron Systems). Source status: test; severity: medium. Source dates: 2023-04-17 / 2023-12-04.

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

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: 9f07f7851b4ac73d6b9a956cea7a9673bb31a438790c073d54fdd759bb2f0e68

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: Add Potential Suspicious New Download Source To Winget
id: c15a46a0-07d4-4c87-b4b6-89207835a83b
related:
    - id: 05ebafc8-7aa2-4bcd-a269-2aec93f9e842
      type: similar
    - id: 81a0ecb5-0a41-4ba1-b2ba-c944eb92bfa2
      type: similar
status: test
description: Detects usage of winget to add new potentially suspicious download sources
references:
    - https://learn.microsoft.com/en-us/windows/package-manager/winget/source
    - https://github.com/nasbench/Misc-Research/tree/b9596e8109dcdb16ec353f316678927e507a5b8d/LOLBINs/Winget
author: Nasreddine Bencherchali (Nextron Systems)
date: 2023-04-17
modified: 2023-12-04
tags:
    - attack.execution
    - attack.t1059
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - Image|endswith: '\winget.exe'
        - OriginalFileName: 'winget.exe'
    selection_cli:
        CommandLine|contains|all:
            - 'source '
            - 'add '
    selection_source_direct_ip:
        # This is a best effort. A better way to handle this is to limit it via whitelist. Check Group Policy for more details
        CommandLine|re: '://\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}'
    condition: all of selection_*
falsepositives:
    - Unknown
level: medium

Original YAML and metadata in JSON

False positives

• Unknown

Source references

• https://learn.microsoft.com/en-us/windows/package-manager/winget/source
• https://github.com/nasbench/Misc-Research/tree/b9596e8109dcdb16ec353f316678927e507a5b8d/LOLBINs/Winget