Potential Network Sniffing Activity Using Network Tools

Status: test
Severity: medium
Log source: category process_creation, product windows
Author: Timur Zinniatullin, oscd.community, Nasreddine Bencherchali (Nextron Systems)
Source: github.com/SigmaHQ/sigma

Detects potential network sniffing via use of network tools such as "tshark", "windump". Network sniffing refers to using the network interface on a system to monitor or capture information sent over a wired or wireless connection. An adversary may place a network interface into promiscuous mode to passively access data in transit over the network, or use span ports to capture a larger amount of data.

Known false positives

Legitimate administration activity to troubleshoot network issues

MITRE ATT&CK coverage

Tactic	Techniques
Credential Access	`T1040` Network Sniffing
Discovery	`T1040` Network Sniffing

Telemetry coverage

Provider	Record / event type
Sysmon	Event ID 1: Process creation
Security-Auditing	Event ID 4688: A new process has been created.

Rule body

title: Potential Network Sniffing Activity Using Network Tools
id: ba1f7802-adc7-48b4-9ecb-81e227fddfd5
status: test
description: |
    Detects potential network sniffing via use of network tools such as "tshark", "windump".
    Network sniffing refers to using the network interface on a system to monitor or capture information sent over a wired or wireless connection.
    An adversary may place a network interface into promiscuous mode to passively access data in transit over the network, or use span ports to capture a larger amount of data.
references:
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1040/T1040.md
author: Timur Zinniatullin, oscd.community, Nasreddine Bencherchali (Nextron Systems)
date: 2019-10-21
modified: 2023-02-20
tags:
    - attack.credential-access
    - attack.discovery
    - attack.t1040
logsource:
    category: process_creation
    product: windows
detection:
    selection_tshark:
        Image|endswith: '\tshark.exe'
        CommandLine|contains: '-i'
    selection_windump:
        Image|endswith: '\windump.exe'
    condition: 1 of selection_*
falsepositives:
    - Legitimate administration activity to troubleshoot network issues
level: medium

Stages and Predicates

Stage 0: `condition`

1 of selection_*

Stage 1: `selection_tshark`

selection_tshark:
    Image|endswith: '\tshark.exe'
    CommandLine|contains: '-i'

Stage 2: `selection_windump`

selection_windump:
    Image|endswith: '\windump.exe'

Indicators

These rows show field, operator, and value matches.

Field	Kind	Values	Search
`CommandLine`	match	`-i` corpus 7 (sigma 7)	`field:"CommandLine" kind:match value:"-i"`
`Image`	ends_with	`\tshark.exe` `\windump.exe`	`field:"Image" kind:ends_with`