What happened

The PAM configuration file {{ @file.path }} was modified by the process {{ @process.comm }}, potentially to manipulate authentication procedures.

Goal

Detect modifications to pam.d directory.

Strategy

Linux Pluggable Authentication Modules (PAM) provide authentication for applications and services. Authentication modules in the PAM system are setup and configured under the /etc/pam.d/ directory. An attacker may attempt to modify or add an authentication module in PAM in order to bypass the authentication process, or reveal system credentials.

Triage and response

1. Identify if the changes to the path {{@file.path}} were part of known system setup or mainenance.
2. If these changes were unauthorized, roll back the host in question to a known good PAM configuration, or replace the system with a known-good system image.

Required Agent version 7.27 or higher