WebDAV Delivery of Executable Files over HTTP (Zeek)

Flags Zeek HTTP events where WebDAV traffic serves an .exe with MIME type 'dosexec'.

FreeReviewedSigma · Medium · v2
Product
zeek
Service
http
Author
SOC Prime, Adam Swan (SigmaHQ), DRL 1.1
Published
2020-05-01
Updated
2026-07-31
title: WebDAV Delivery of Executable Files over HTTP (Zeek)
id: 8a5063d6-4887-4393-9f0c-6c9efc5277d5
status: test
description: This rule flags HTTP sessions where the client appears to use WebDAV and the requested URI targets an executable. It correlates a WebDAV user agent/URI indicator with a response MIME type containing "dosexec" and a URI ending in ".exe". Attackers may use WebDAV to stage and deliver binaries for follow-on execution, so matching this behavior helps identify potential command-and-control or initial payload transfer. It relies on Zeek HTTP telemetry fields including client user agent, request URI, and response MIME types.
references:
  - http://carnal0wnage.attackresearch.com/2012/06/webdav-server-to-download-custom.html
  - https://github.com/OTRF/detection-hackathon-apt29
  - https://github.com/SigmaHQ/sigma/blob/master/rules/network/zeek/zeek_http_executable_download_from_webdav.yml
author: SOC Prime, Adam Swan, Huntrule Team
date: 2020-05-01
modified: 2021-11-27
tags:
  - attack.command-and-control
  - attack.t1105
logsource:
  product: zeek
  service: http
detection:
  selection_webdav:
    - c-useragent|contains: WebDAV
    - c-uri|contains: webdav
  selection_executable:
    - resp_mime_types|contains: dosexec
    - c-uri|endswith: .exe
  condition: selection_webdav and selection_executable
falsepositives:
  - Unknown
level: medium
license: DRL-1.1
related:
  - id: aac2fd97-bcba-491b-ad66-a6edf89c71bf
    type: derived