Remote Access Tool - Team Viewer Session Started On Windows Host

Status: test
Severity: low
Log source: category process_creation, product windows
Author: Josh Nickels, Qi Nan
Source: github.com/SigmaHQ/sigma

Detects the command line executed when TeamViewer starts a session started by a remote host. Once a connection has been started, an investigator can verify the connection details by viewing the "incoming_connections.txt" log file in the TeamViewer folder.

Known false positives

Legitimate usage of TeamViewer

MITRE ATT&CK coverage

Tactic	Techniques
Initial Access	`T1133` External Remote Services
Persistence	`T1133` External Remote Services

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: Remote Access Tool - Team Viewer Session Started On Windows Host
id: ab70c354-d9ac-4e11-bbb6-ec8e3b153357
related:
    - id: 1f6b8cd4-3e60-47cc-b282-5aa1cbc9182d
      type: similar
    - id: f459ccb4-9805-41ea-b5b2-55e279e2424a
      type: similar
status: test
description: |
    Detects the command line executed when TeamViewer starts a session started by a remote host.
    Once a connection has been started, an investigator can verify the connection details by viewing the "incoming_connections.txt" log file in the TeamViewer folder.
references:
    - Internal Research
author: Josh Nickels, Qi Nan
date: 2024-03-11
tags:
    - attack.persistence
    - attack.initial-access
    - attack.t1133
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        Image: 'TeamViewer_Desktop.exe'
        ParentImage: 'TeamViewer_Service.exe'
        CommandLine|endswith: 'TeamViewer_Desktop.exe --IPCport 5939 --Module 1'
    condition: selection
falsepositives:
    - Legitimate usage of TeamViewer
level: low

Stages and Predicates

Stage 0: `condition`

selection

Stage 1: `selection`

selection:
    Image: 'TeamViewer_Desktop.exe'
    ParentImage: 'TeamViewer_Service.exe'
    CommandLine|endswith: 'TeamViewer_Desktop.exe --IPCport 5939 --Module 1'

Indicators

These rows show field, operator, and value matches.

Field	Kind	Values	Search
`CommandLine`	ends_with	`TeamViewer_Desktop.exe --IPCport 5939 --Module 1`	`field:"CommandLine" kind:ends_with value:"TeamViewer_Desktop.exe --IPCport 5939 --Module 1"`
`Image`	eq	`TeamViewer_Desktop.exe`	`field:"Image" kind:eq value:"TeamViewer_Desktop.exe"`
`ParentImage`	eq	`TeamViewer_Service.exe`	`field:"ParentImage" kind:eq value:"TeamViewer_Service.exe"`