Linux Auditd Auditd Daemon Abort

name: Linux Auditd Auditd Daemon Abort
id: 76d6573f-c4ab-4fa1-8390-c036416d4add
version: 6
creation_date: '2024-08-12'
modification_date: '2026-05-13'
author: Teoderick Contreras, Splunk
status: production
type: Anomaly
description: The following analytic detects the abnormal termination of the Linux audit daemon (auditd) by identifying DAEMON_ABORT events in audit logs. These terminations suggest a serious failure of the auditing subsystem, potentially due to resource exhaustion, corruption, or malicious interference. Unlike a clean shutdown, DAEMON_ABORT implies that audit logging may have been disabled without system administrator intent. Alerts should be generated on detection and correlated with DAEMON_START, DAEMON_END, and system logs to determine root cause. If no DAEMON_START follows soon after, or this pattern repeats, it indicates a high-severity issue that impacts log integrity and should be immediately investigated.
data_source:
    - Linux Auditd Daemon Abort
search: |-
    `linux_auditd` type=DAEMON_ABORT
      | rename host as dest
      | stats count min(_time) as firstTime max(_time) as lastTime
        BY type op res
           uid dest pid
      | `security_content_ctime(firstTime)`
      | `security_content_ctime(lastTime)`
      | `linux_auditd_auditd_daemon_abort_filter`
how_to_implement: To implement this detection, the process begins by ingesting auditd data, that consist SYSCALL, TYPE, EXECVE and PROCTITLE events, which captures command-line executions and process details on Unix/Linux systems. These logs should be ingested and processed using Splunk Add-on for Unix and Linux (https://splunkbase.splunk.com/app/833), which is essential for correctly parsing and categorizing the data. The next step involves normalizing the field names  to match the field names set by the Splunk Common Information Model (CIM) to ensure consistency across different data sources and enhance the efficiency of data modeling. This approach enables effective monitoring and detection of linux endpoints where auditd is deployed
known_false_positives: Administrator or network operator can use this application for automation purposes. Please update the filter macros to remove false positives.
references:
    - https://docs.redhat.com/en/documentation/red_hat_enterprise_linux/6/html/security_guide/sec-audit_record_types
drilldown_searches:
    - name: View the detection results for - "$dest$"
      search: '%original_detection_search% | search  dest = "$dest$"'
      earliest_offset: $info_min_time$
      latest_offset: $info_max_time$
    - name: View risk events for the last 7 days for - "$dest$"
      search: '| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$dest$") | stats count min(_time) as firstTime max(_time) as lastTime values(search_name) as "Search Name" values(risk_message) as "Risk Message" values(analyticstories) as "Analytic Stories" values(annotations._all) as "Annotations" values(annotations.mitre_attack.mitre_tactic) as "ATT&CK Tactics" by normalized_risk_object | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`'
      earliest_offset: 7d
      latest_offset: "0"
intermediate_findings:
    entities:
        - field: dest
          type: system
          score: 20
          message: Auditd service event - [$type$] event occurred on host - [$dest$].
analytic_story:
    - Compromised Linux Host
asset_type: Endpoint
mitre_attack_id:
    - T1685.004
product:
    - Splunk Enterprise
    - Splunk Enterprise Security
    - Splunk Cloud
category: endpoint
security_domain: endpoint
tests:
    - name: True Positive Test
      attack_data:
        - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1562.012/auditd_daemon_type/linux_auditd_daemon.log
          source: auditd
          sourcetype: auditd
      test_type: unit