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.
- Product
- linux
- Service
- auditd
- Author
- Pawel Mazur (SigmaHQ), DRL 1.1
- Published
- 2021-09-03
- Updated
- 2026-07-31
ATT&CK techniques
DiscoveryRecon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
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
Changelog
v3- v3Candidate ingested via manual entry.2026-07-31
- v2Candidate ingested via manual entry.2026-07-31
- v1No 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.
title: Linux auditd System Information Discovery via uname, uptime, lsmod, hostname, env, and release file reads
id: 681bd37c-1251-4372-a286-9c0108aeec27
status: test
description: 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.
references:
- https://github.com/redcanaryco/atomic-red-team/blob/f296668303c29d3f4c07e42bdd2b28d8dd6625f9/atomics/T1082/T1082.md
- https://github.com/SigmaHQ/sigma/blob/master/rules/linux/auditd/lnx_auditd_system_info_discovery.yml
author: Pawel Mazur, Huntrule Team
date: 2021-09-03
modified: 2023-03-06
tags:
- attack.discovery
- attack.t1082
logsource:
product: linux
service: auditd
detection:
selection_1:
type: PATH
name:
- /etc/lsb-release
- /etc/redhat-release
- /etc/issue
selection_2:
type: EXECVE
a0:
- uname
- uptime
- lsmod
- hostname
- env
selection_3:
type: EXECVE
a0: grep
a1|contains:
- vbox
- vm
- xen
- virtio
- hv
selection_4:
type: EXECVE
a0: kmod
a1: list
condition: 1 of selection_*
falsepositives:
- Likely
level: low
license: DRL-1.1
related:
- id: f34047d9-20d3-4e8b-8672-0a35cc50dc71
type: derived