Windows network connection from process running in suspicious or uncommon file paths

Alerts on Windows network connections initiated by processes executing from suspicious or uncommon directories.

FreeReviewedSigma · High · v2
Product
windows
Category
network_connection
Author
Florian Roth (Nextron Systems), Nasreddine Bencherchali (Nextron Systems) (SigmaHQ), DRL 1.1
Published
2017-03-19
Updated
2026-07-31

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. Exfiltration

  13. Impact

What it detects

This rule flags Windows network connections where the initiating process is running from a suspicious or uncommon file system location (for example, recycle bin, temp directories, default/public user folders, and various Windows subpaths). Attackers frequently execute or stage payloads from such locations to evade normal allowlists and blend into transient or user-writable areas before command-and-control communication. It relies on telemetry indicating the network connection was initiated and the process image path, including substring matches against known suspicious directory patterns, while excluding several common destination host domains.

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Windows network connection from process running in suspicious or uncommon file paths
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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.