Modification of Standard Authentication Module or Configuration

Last updated 7 months ago on 2025-01-15
Created 5 years ago on 2020-12-21

About

Adversaries may modify the standard authentication module for persistence via patching the normal authorization process or modifying the login configuration to allow unauthorized access or elevate privileges.
Tags
Domain: EndpointOS: macOSOS: LinuxUse Case: Threat DetectionTactic: Credential AccessTactic: PersistenceData Source: Elastic DefendLanguage: kuery
Severity
medium
Risk Score
47
MITRE ATT&CK™

Persistence (TA0003)(opens in a new tab or window)

Credential Access (TA0006)(opens in a new tab or window)

False Positive Examples
Trusted system module updates or allowed Pluggable Authentication Module (PAM) daemon configuration changes.
License
Elastic License v2(opens in a new tab or window)

Definition

Rule Type
New Terms Rule
Integration Pack
Prebuilt Security Detection Rules
Index Patterns
auditbeat-*logs-endpoint.events.*
Related Integrations

endpoint(opens in a new tab or window)

Query
event.category:file and event.type:change and
  (file.name:pam_*.so or file.path:(/etc/pam.d/* or /private/etc/pam.d/* or /usr/lib64/security/*)) and
  process.executable:
    (* and
      not
      (
        /usr/libexec/packagekitd or
        /usr/bin/vim or
        /usr/libexec/xpcproxy or
        /usr/bin/bsdtar or
        /usr/local/bin/brew or
        "/System/Library/PrivateFrameworks/PackageKit.framework/Versions/A/XPCServices/package_script_service.xpc/Contents/MacOS/package_script_service"
      )
    ) and
  not file.path:
         (
           /tmp/snap.rootfs_*/pam_*.so or
           /tmp/newroot/lib/*/pam_*.so or
           /private/var/folders/*/T/com.apple.fileprovider.ArchiveService/TemporaryItems/*/lib/security/pam_*.so or
           /tmp/newroot/usr/lib64/security/pam_*.so
         ) and
  not process.name:
         (
           yum or dnf or rsync or platform-python or authconfig or rpm or pdkg or apk or dnf-automatic or btrfs or
           dpkg or pam-auth-update or steam or platform-python3.6 or pam-config or microdnf or yum_install or yum-cron or
           systemd or containerd or pacman
         )

Install detection rules in Elastic Security

Detect Modification of Standard Authentication Module or Configuration 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).