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Linux Netcat Execution with -e/-c Launching Common Shells

Alerts on Linux executions of nc/ncat using -e that reference common shells, indicating potential reverse-shell setup.

FreeReviewedSigma · High · v4
Product
linux
Category
process_creation
Author
@d4ns4n_, Nasreddine Bencherchali (Nextron Systems) (SigmaHQ), DRL 1.1
Published
2023-04-07
Updated
2026-09-24
AnalysisDetection

ATT&CK techniques

Execution

  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 identifies Linux process executions where a netcat binary (including common nc/ncat paths and variants) is invoked with command-line flags -e or -c and followed by typical shell interpreters. Attackers often use this pattern to spawn a shell over the network, enabling interactive remote access. The detection relies on process creation telemetry with the executable image name and the full command-line content to match the netcat variant, the -e/-c flags, and common shell paths or names.

Reporting behind it

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Linux Netcat Execution with -e/-c Launching Common Shells
Pivot detection · T1059 · 9 related

Changelog

v4
  1. v4
    Candidate ingested via manual entry.2026-09-24
  2. v2
    Candidate ingested via manual entry.2026-07-31
  3. 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.