Detection rules › Sigma

Windows Internet Hosted WebDav Share Mount Via Net.EXE

Status
test
Severity
high
Log source
product windows, category process_creation
Author
Nasreddine Bencherchali (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects when an internet hosted webdav share is mounted using the "net.exe" utility

MITRE ATT&CK coverage

Event coverage

ProviderEventTitle
SysmonEvent ID 1Process creation

Rule body yaml

title: Windows Internet Hosted WebDav Share Mount Via Net.EXE
id: 7e6237fe-3ddb-438f-9381-9bf9de5af8d0
status: test
description: Detects when an internet hosted webdav share is mounted using the "net.exe" utility
references:
    - https://drive.google.com/file/d/1lKya3_mLnR3UQuCoiYruO3qgu052_iS_/view
author: Nasreddine Bencherchali (Nextron Systems)
date: 2023-02-21
modified: 2023-07-25
tags:
    - attack.lateral-movement
    - attack.t1021.002
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - Image|endswith:
              - '\net.exe'
              - '\net1.exe'
        - OriginalFileName:
              - 'net.exe'
              - 'net1.exe'
    selection_cli:
        CommandLine|contains|all:
            - ' use '
            - ' http'
    condition: all of selection_*
falsepositives:
    - Unknown
level: high

Stages and Predicates

Stage 0: condition

all of selection_*

Stage 1: selection_img

selection_img:
    - Image|endswith:
          - '\net.exe'
          - '\net1.exe'
    - OriginalFileName:
          - 'net.exe'
          - 'net1.exe'

Stage 2: selection_cli

selection_cli:
    CommandLine|contains|all:
        - ' use '
        - ' http'

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
CommandLinematch
  • http corpus 3 (sigma 2, chronicle 1)
  • use corpus 6 (sigma 6)
Imageends_with
  • \net.exe corpus 49 (sigma 49)
  • \net1.exe corpus 47 (sigma 47)
OriginalFileNameeq
  • net.exe corpus 28 (sigma 19, elastic 7, splunk 2)
  • net1.exe corpus 44 (sigma 19, splunk 19, elastic 6)