Detect IDE Tunneling in Sumo Logic CSE
Adversaries may abuse Integrated Development Environment (IDE) software with remote development features to establish an interactive command and control channel on target systems within a network. IDE tunneling combines SSH, port forwarding, file sharing, and debugging into a single secure connection, letting developers work on remote systems as if they were local. Unlike SSH and port forwarding, IDE tunneling encapsulates an entire session and may use proprietary tunneling protocols alongside SSH, allowing adversaries to blend in with legitimate development workflows. Some IDEs, like Visual Studio Code, provide CLI tools (e.g., code tunnel) that adversaries may use to programmatically establish tunnels and generate web-accessible URLs for remote access. These tunnels can be authenticated through accounts such as GitHub, enabling the adversary to control the compromised system via a legitimate developer portal.
MITRE ATT&CK
- Tactic
- Command and Control
- Technique
- T1219 Remote Access Tools
- Sub-technique
- T1219.001 IDE Tunneling
- Canonical reference
- https://attack.mitre.org/techniques/T1219/001/
Sumo Detection Query
(_sourceCategory="*sysmon*" OR _sourceCategory="*windows/sysmon*" OR _sourceCategory="*endpoint/process*")
| where EventID = "1"
| where (
toLowerCase(Image) matches /.*?(code\.exe|code-tunnel\.exe|code-insiders\.exe|code-tunnel|devtunnel\.exe|devtunnel|jetbrains-gateway\.exe|gateway\.exe|remote-dev-server\.sh|idea\.sh|pycharm\.sh|cursor\.exe|windsurf\.exe)$/
or toLowerCase(CommandLine) contains "tunnel"
or toLowerCase(CommandLine) contains "serve-web"
or toLowerCase(CommandLine) contains "--remote-tunnel"
or toLowerCase(CommandLine) contains "dev-tunnel"
or toLowerCase(CommandLine) contains "--host 0.0.0.0"
or toLowerCase(CommandLine) contains "--accept-server-license-terms"
)
| eval IsTunnelCommand = if (toLowerCase(CommandLine) contains "tunnel", "true", "false")
| eval IsCodeCLI = if (toLowerCase(Image) matches /.*?(code\.exe|code-tunnel\.exe|code-insiders\.exe|code-tunnel)$/, "true", "false")
| eval IsJetBrains = if (toLowerCase(Image) matches /.*?(jetbrains-gateway\.exe|gateway\.exe|remote-dev-server\.sh|idea\.sh|pycharm\.sh)$/, "true", "false")
| eval HasGitHubAuth = if (toLowerCase(CommandLine) contains "github" or toLowerCase(CommandLine) contains "--provider github", "true", "false")
| eval IsHeadless = if (
toLowerCase(CommandLine) contains "--no-browser"
or toLowerCase(CommandLine) contains "--accept-server-license-terms"
or toLowerCase(CommandLine) contains "serve-web"
or toLowerCase(CommandLine) contains "--cli", "true", "false")
| fields _messagetime, Computer, User, Image, CommandLine, ParentImage, ParentCommandLine, IsTunnelCommand, IsCodeCLI, IsJetBrains, HasGitHubAuth, IsHeadless
| sort by _messagetime descDetects IDE tunneling activity (T1219.001) in Sumo Logic by parsing Sysmon EventID 1 (Process Create) logs for known IDE tunnel binaries and suspicious command-line patterns. Enriches each event with Boolean classification flags covering tunnel command presence, IDE family, GitHub authentication, and headless/server-mode operation to support analyst triage.
Data Sources
Required Tables
False Positives & Tuning
- Developers on engineering teams running VS Code with Remote Tunnels or JetBrains Gateway enabled as an approved tool for cloud-based development environments, generating matching process events from known developer workstations.
- Automated CI/CD build agents invoking devtunnel or code-tunnel to expose ephemeral preview environments for pull request review workflows, appearing as service account process launches.
- Corporate help desk using Cursor or VS Code with remote development features to access end-user machines during IT support sessions conducted under a formal access request process.
Other platforms for T1219.001
Testing Methodology
Validate this detection against 3 adversary techniques from Atomic Red Team. Each test below lists the behaviour to exercise and the telemetry you should expect to see. Executable commands and cleanup steps are available with Pro.
- Test 1VS Code CLI Tunnel Initiation
Expected signal: Sysmon Event ID 1: Process Create with Image=code.exe, CommandLine containing 'tunnel --accept-server-license-terms --name test-tunnel'. Sysmon Event ID 22: DNS query for tunnels.api.visualstudio.com. If tunnel starts: Sysmon Event ID 3 for HTTPS connection to tunnel relay servers.
- Test 2DevTunnel CLI Tunnel Creation
Expected signal: Sysmon Event ID 1: Process Create with Image=devtunnel.exe, CommandLine containing 'host --port 8080 --allow-anonymous'. Sysmon Event ID 22: DNS query for devtunnels.ms. Sysmon Event ID 3: Network connection to Microsoft tunnel infrastructure.
- Test 3VS Code Tunnel Persistence via Scheduled Task
Expected signal: Security Event ID 4698: Scheduled task created with TaskContent containing 'code.exe tunnel'. Sysmon Event ID 1: Process Create for schtasks.exe with command line showing the tunnel command. The scheduled task itself won't execute (non-existent path) but the creation event fires.
References (8)
- https://attack.mitre.org/techniques/T1219/001/
- https://www.sentinelone.com/labs/operation-digital-eye-chinese-apt-compromises-critical-digital-infrastructure-via-visual-studio-code-tunnels/
- https://unit42.paloaltonetworks.com/stately-taurus-abuses-vscode-southeast-asian-espionage/
- https://medium.com/@truvis.thornton/visual-studio-code-embedded-reverse-shell-and-how-to-block-create-sentinel-detection-and-add-e864ebafaf6d
- https://learn.microsoft.com/en-us/azure/developer/dev-tunnels/overview
- https://code.visualstudio.com/docs/remote/tunnels
- https://learn.microsoft.com/en-us/defender-endpoint/advanced-hunting-deviceprocessevents-table
- https://github.com/SigmaHQ/sigma/tree/master/rules/windows/process_creation
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