Potential Binary Proxy Execution Via VSDiagnostics.EXE

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

Detects execution of "VSDiagnostics.exe" with the "start" command in order to launch and proxy arbitrary binaries.

Known false positives

Legitimate usage for tracing and diagnostics purposes

MITRE ATT&CK coverage

Tactic	Techniques
Stealth	`T1218` System Binary Proxy Execution

Telemetry coverage

Provider	Record / event type
Sysmon	Event ID 1: Process creation

Rule body

title: Potential Binary Proxy Execution Via VSDiagnostics.EXE
id: ac1c92b4-ac81-405a-9978-4604d78cc47e
status: test
description: Detects execution of "VSDiagnostics.exe" with the "start" command in order to launch and proxy arbitrary binaries.
references:
    - https://twitter.com/0xBoku/status/1679200664013135872
author: Nasreddine Bencherchali (Nextron Systems)
date: 2023-08-03
tags:
    - attack.stealth
    - attack.t1218
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - Image|endswith: '\VSDiagnostics.exe'
        - OriginalFileName: 'VSDiagnostics.exe'
    selection_cli_start:
        CommandLine|contains: 'start'
    selection_cli_launch:
        CommandLine|contains:
            - ' /launch:'
            - ' -launch:'
    condition: all of selection_*
falsepositives:
    - Legitimate usage for tracing and diagnostics purposes
level: medium

Stages and Predicates

Stage 0: `condition`

all of selection_*

Stage 1: `selection_img`

selection_img:
    - Image|endswith: '\VSDiagnostics.exe'
    - OriginalFileName: 'VSDiagnostics.exe'

Stage 2: `selection_cli_start`

selection_cli_start:
    CommandLine|contains: 'start'

Stage 3: `selection_cli_launch`

selection_cli_launch:
    CommandLine|contains:
        - ' /launch:'
        - ' -launch:'

Indicators

These rows show field, operator, and value matches.

Field	Kind	Values	Search
`CommandLine`	match	`-launch:` `/launch:` `start` corpus 13 (sigma 11, splunk 2)	`field:"CommandLine" kind:match`
`Image`	ends_with	`\VSDiagnostics.exe`	`field:"Image" kind:ends_with value:"\VSDiagnostics.exe"`
`OriginalFileName`	eq	`VSDiagnostics.exe`	`field:"OriginalFileName" kind:eq value:"VSDiagnostics.exe"`

Potential Binary Proxy Execution Via VSDiagnostics.EXE

Known false positives

MITRE ATT&CK coverage

Telemetry coverage

Rule body

Stages and Predicates

Stage 0: condition

Stage 1: selection_img

Stage 2: selection_cli_start

Stage 3: selection_cli_launch

Indicators

Stage 0: `condition`

Stage 1: `selection_img`

Stage 2: `selection_cli_start`

Stage 3: `selection_cli_launch`