huntrule

Linux auditd System Information Discovery via uname, uptime, lsmod, hostname, env, and release file reads

Triggers on auditd events showing host enumeration commands and system identity file access on Linux.

FreeReviewedSigma · Low · v3
Product
linux
Service
auditd
Author
Pawel Mazur (SigmaHQ), DRL 1.1
Published
2021-09-03
Updated
2026-07-31
AnalysisDetection

ATT&CK techniques

Discovery

  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 Linux processes and file access indicative of system information discovery, including reads of common release/issue files and execution of utilities such as uname, uptime, lsmod, hostname, env, and kmod list. It also matches grep output patterns that may reveal virtualization or hypervisor-related strings (e.g., vbox, vm, xen, virtio, hv). These actions can help an attacker profile a host for targeting decisions, and the detection relies on auditd telemetry for file PATH access and execve command arguments.

Reporting behind it

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Suspicious System Discovery via WMIC Query Commands (via process_creation)
Suspicious PowerShell Host and Locale Reconnaissance via MuddyWater Tsundere Botnet
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Suspicious System Profiler Hardware Reconnaissance via BANSHEE
Linux auditd System Information Discovery via uname, uptime, lsmod, hostname, env, and release file reads
Pivot detection · T1082 · 9 related

Changelog

v3
  1. v3
    Candidate ingested via manual entry.2026-07-31
  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.