Windows: Detect creation of code_tunnel.json indicating VS Code tunneling utility use
Alerts on Windows file creation of code_tunnel.json, indicating VS Code tunneling may be active.
FreeReviewedSigma · Medium · v5
- Product
- windows
- Category
- file_event
- Author
- Nasreddine Bencherchali (Nextron Systems) (SigmaHQ), DRL 1.1
- Published
- 2023-10-25
- Updated
- 2026-07-31
What it detects
This rule identifies when a file ending with '\code_tunnel.json' is created on Windows, which indicates use of the VS Code tunneling utility. Attackers may abuse tunneling features to establish external connectivity that can support command and control. It relies on file creation telemetry capturing the target filename suffix.
Reporting behind it
Changelog
v5- v5Candidate ingested via manual entry.2026-07-31
- v4Candidate ingested via manual entry.2026-07-31
- v3Candidate ingested via manual entry.2026-07-31
- v2Candidate ingested via manual entry.2026-07-31
- v1No changelog recorded for this version.2026-07-30
Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.
windows-file-create-of-code-tunnel-json-indicates-vs-code-tunneling-usage-9661ec9d
title: "Windows: Detect creation of code_tunnel.json indicating VS Code tunneling utility use"
id: e8cd6686-7542-4be1-af01-75af7f0000e6
status: test
description: This rule identifies when a file ending with '\code_tunnel.json' is created on Windows, which indicates use of the VS Code tunneling utility. Attackers may abuse tunneling features to establish external connectivity that can support command and control. It relies on file creation telemetry capturing the target filename suffix.
references:
- https://ipfyx.fr/post/visual-studio-code-tunnel/
- https://badoption.eu/blog/2023/01/31/code_c2.html
- https://github.com/SigmaHQ/sigma/blob/master/rules-threat-hunting/windows/file/file_event/file_event_win_vscode_tunnel_indicators.yml
author: Nasreddine Bencherchali (Nextron Systems), Huntrule Team
date: 2023-10-25
tags:
- attack.command-and-control
- detection.threat-hunting
logsource:
category: file_event
product: windows
detection:
selection:
TargetFilename|endswith: \code_tunnel.json
condition: selection
falsepositives:
- Legitimate usage of VsCode tunneling functionality will also trigger this
level: medium
license: DRL-1.1
related:
- id: 9661ec9d-4439-4a7a-abed-d9be4ca43b6d
type: derived