Windows Proxy Activity Using Microsoft-WebDAV-MiniRedir GET User-Agent

Alerts on proxy HTTP GET requests using the Microsoft-WebDAV-MiniRedir/ User-Agent prefix associated with file download behavior.

FreeReviewedSigma · High · v2
Category
proxy
Author
Florian Roth (Nextron Systems) (SigmaHQ), DRL 1.1
Published
2018-04-06
Updated
2026-07-31
title: Windows Proxy Activity Using Microsoft-WebDAV-MiniRedir GET User-Agent
id: 9bc33e11-50ed-46de-8a3d-d1e61af1f092
status: test
description: This rule flags proxy traffic where the HTTP method is GET and the User-Agent starts with Microsoft-WebDAV-MiniRedir/, indicating WebDAV-style download behavior. Attackers commonly use WebDAV interfaces to stage or retrieve payloads from remote servers, so this User-Agent pattern can be a high-signal indicator of command-and-control activity. The detection relies on proxy logs capturing HTTP method and User-Agent fields.
references:
  - https://mgreen27.github.io/posts/2018/04/02/DownloadCradle.html
  - https://github.com/SigmaHQ/sigma/blob/master/rules/web/proxy_generic/proxy_downloadcradle_webdav.yml
author: Florian Roth (Nextron Systems), Huntrule Team
date: 2018-04-06
modified: 2021-11-27
tags:
  - attack.command-and-control
  - attack.t1071.001
logsource:
  category: proxy
detection:
  selection:
    c-useragent|startswith: Microsoft-WebDAV-MiniRedir/
    cs-method: GET
  condition: selection
falsepositives:
  - Administrative scripts that download files from the Internet
  - Administrative scripts that retrieve certain website contents
  - Legitimate WebDAV administration
level: high
license: DRL-1.1
related:
  - id: e09aed7a-09e0-4c9a-90dd-f0d52507347e
    type: derived