Elastic Security Detection Rules

Potential Suspicious DebugFS Root Device Access

Last updated 6 months ago on 2025-02-04
Created 2 years ago on 2023-08-30

About

This rule monitors for the usage of the built-in Linux DebugFS utility to access a disk device without root permissions. Linux users that are part of the "disk" group have sufficient privileges to access all data inside of the machine through DebugFS. Attackers may leverage DebugFS in conjunction with "disk" permissions to read sensitive files owned by root, such as the shadow file, root ssh private keys or other sensitive files that may allow them to further escalate privileges.
Tags
Domain: EndpointOS: LinuxUse Case: Threat DetectionTactic: Privilege EscalationData Source: Elastic DefendLanguage: eql
Severity
low
Risk Score
21
MITRE ATT&CK™

Privilege Escalation (TA0004)(opens in a new tab or window)

↳ Valid Accounts (T1078)(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.process*
Related Integrations

endpoint(opens in a new tab or window)

Query
process where host.os.type == "linux" and event.type == "start" and event.action == "exec" and
process.name == "debugfs" and process.args : "/dev/sd*" and not process.args == "-R" and
not user.Ext.real.id == "0" and not group.Ext.real.id == "0"

Install detection rules in Elastic Security

Detect Potential Suspicious DebugFS Root Device Access 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).