huntrule

Windows DNS Queries to Visual Studio Code Tunnel Domains

Alerts on Windows DNS queries to .tunnels.api.visualstudio.com, matching Visual Studio Code tunnel endpoints.

FreeReviewedSigma · Medium · v2
Product
windows
Category
dns_query
Author
citron_ninja (SigmaHQ), DRL 1.1
Published
2023-10-25
Updated
2026-07-31
AnalysisDetection

ATT&CK techniques

C2

  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Persistence

  6. Priv Esc

  7. Defense Evasion

  8. Cred Access

  9. Discovery

  10. Lateral Movement

  11. Collection

  12. C2

  13. Exfiltration

  14. Impact

What it detects

This rule flags DNS query events where the queried name ends with .tunnels.api.visualstudio.com on Windows systems. Such domains can be used by attackers to reach externally hosted endpoints, potentially enabling command-and-control or persistence. The detection relies on DNS query telemetry that includes the queried domain name (QueryName).

Reporting behind it

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Suspicious Network Connection From wabmig.exe (Turian Injection)
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Windows DNS Queries to Visual Studio Code Tunnel Domains
Pivot detection · T1071.001 · 9 related

Changelog

v2
  1. v2
    Candidate ingested via manual entry.2026-07-31
  2. v1
    No 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.