Elastic Security Detection Rules

Potential Hidden Process via Mount Hidepid

Last updated a month ago on 2024-10-17
Created 2 years ago on 2023-04-11

About

Identifies the execution of mount process with hidepid parameter, which can make processes invisible to other users from the system. Adversaries using Linux kernel version 3.2+ (or RHEL/CentOS v6.5+ above) can hide the process from other users. When hidepid=2 option is executed to mount the /proc filesystem, only the root user can see all processes and the logged-in user can only see their own process. This provides a defense evasion mechanism for the adversaries to hide their process executions from all other commands such as ps, top, pgrep and more. With the Linux kernel hardening hidepid option all the user has to do is remount the /proc filesystem with the option, which can now be monitored and detected.
Tags
Domain: EndpointOS: LinuxUse Case: Threat DetectionTactic: Defense EvasionData Source: Elastic EndgameData Source: Elastic DefendData Source: Auditd Manager
Severity
medium
Risk Score
47
MITRE ATT&CK™

Defense Evasion (TA0005)(opens in a new tab or window)

↳ Hide Artifacts (T1564)(opens in a new tab or window)

License
Elastic License v2(opens in a new tab or window)

Definition

Rule Type
Event Correlation Rule
Integration Pack
Prebuilt Security Detection Rules
Index Patterns
logs-endpoint.events.*endgame-*auditbeat-*logs-auditd_manager.auditd-*
Related Integrations

endpoint(opens in a new tab or window)

auditd_manager(opens in a new tab or window)

Query
process where host.os.type == "linux" and event.type == "start" and
event.action in ("exec", "exec_event", "executed", "process_started") and
process.name == "mount" and process.args == "/proc" and process.args == "-o" and process.args : "*hidepid=2*" and
not process.parent.command_line like "/opt/cloudlinux/*"

Install detection rules in Elastic Security

Detect Potential Hidden Process via Mount Hidepid in the Elastic Security detection engine by installing this rule into your Elastic Stack.

To setup this rule, check out the installation guide for Prebuilt Security Detection Rules(opens in a new tab or window).