Suspicious Web Shell Spawned via Python or PHP Built-in Server

PremiumReviewedSigma · Medium · v1
Product
linux
Category
process_creation
Author
HuntRule
Published
2026-09-18
Updated
2026-09-18

ATT&CK techniques

Persistence
  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Priv Esc

  6. Defense Evasion

  7. Cred Access

  8. Discovery

  9. Lateral Movement

  10. Collection

  11. C2

  12. Exfiltration

  13. Impact

What it detects

This rule detects launch of a lightweight web server through the Python http.server CGI mode or the PHP built-in development server, a persistence and remote-access technique covered in Elastic Linux persistence research. Attackers stand up these one-line servers to expose a web shell for command execution and file transfer on a compromised host. Such servers spawned outside a development context deserve scrutiny.

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Suspicious Web Shell Spawned via Python or PHP Built-in Server
Pivot detection · T1505.003 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.