IMPORTANT: No additional bug fixes or documentation updates will be released for this version. For the latest information, see the current release documentation.

« Network Connection Initiated by SSHD Child Process Network Connections Initiated Through XDG Autostart Entry »

› ›

Authentication via Unusual PAM Grantor

edit

Authentication via Unusual PAM Grantor

edit

This rule detects successful authentications via PAM grantors that are not commonly used. This could indicate an attacker is attempting to escalate privileges or maintain persistence on the system by modifying the default PAM configuration.

Rule type: new_terms

Rule indices:

auditbeat-*
logs-auditd_manager.auditd-*

Severity: medium

Risk score: 47

Runs every: 5m

Searches indices from: now-9m (Date Math format, see also Additional look-back time)

Maximum alerts per execution: 100

References: None

Tags:

Domain: Endpoint
OS: Linux
Use Case: Threat Detection
Tactic: Credential Access
Tactic: Persistence
Data Source: Auditd Manager

Version: 1

Rule authors:

Elastic

Rule license: Elastic License v2

Setup

edit

Setup

This rule requires the use of the auditd_manager integration. Auditd_manager is a tool designed to simplify and enhance the management of the audit subsystem in Linux systems. It provides a user-friendly interface and automation capabilities for configuring and monitoring system auditing through the auditd daemon. With auditd_manager, administrators can easily define audit rules, track system events, and generate comprehensive audit reports, improving overall security and compliance in the system. The following steps should be executed in order to install and deploy auditd_manager on a Linux system.

Kibana -->
Management -->
Integrations -->
Auditd Manager -->
Add Auditd Manager

Auditd_manager subscribes to the kernel and receives events as they occur without any additional configuration. However, if more advanced configuration is required to detect specific behavior, audit rules can be added to the integration in either the "audit rules" configuration box or the "auditd rule files" box by specifying a file to read the audit rules from. For this detection rule to trigger, no additional configuration is required.

Rule query

edit

event.category:authentication and host.os.type:linux and event.action:authenticated and event.outcome:success and
auditd.data.grantors:(* and not (pam_rootok or *pam_cap* or *pam_permit*))

Framework: MITRE ATT&CK^TM

Tactic:
- Name: Persistence
- ID: TA0003
- Reference URL: https://attack.mitre.org/tactics/TA0003/
Technique:
- Name: Create or Modify System Process
- ID: T1543
- Reference URL: https://attack.mitre.org/techniques/T1543/
Tactic:
- Name: Credential Access
- ID: TA0006
- Reference URL: https://attack.mitre.org/tactics/TA0006/
Technique:
- Name: Modify Authentication Process
- ID: T1556
- Reference URL: https://attack.mitre.org/techniques/T1556/

« Network Connection Initiated by SSHD Child Process Network Connections Initiated Through XDG Autostart Entry »