Detection: GitHub Enterprise Disable Audit Log Event Stream

Updated Date: 2025-01-16 ID: 7bc111cc-7f1b-4be7-99fa-50cf8d2e7564 Author: Patrick Bareiss, Splunk Type: Anomaly Product: Splunk Enterprise Security

Description

The following analytic detects when a user disables audit log event streaming in GitHub Enterprise. The detection monitors GitHub Enterprise audit logs for configuration changes that disable the audit log streaming functionality, which is used to send audit events to security monitoring platforms. This behavior could indicate an attacker attempting to prevent their malicious activities from being logged and detected by disabling the audit trail. For a SOC, identifying the disabling of audit logging is critical as it may be a precursor to other attacks where adversaries want to operate undetected. The impact could be severe as organizations lose visibility into user actions, configuration changes, and security events within their GitHub Enterprise environment, potentially allowing attackers to perform malicious activities without detection. This creates a significant blind spot in security monitoring and incident response capabilities.

1`github_enterprise` action=audit_log_streaming.destroy 
2| fillnull 
3| stats count min(_time) as firstTime max(_time) as lastTime by actor, actor_id, actor_ip, actor_is_bot, actor_location.country_code, business, business_id, user_agent, action 
4| eval user=actor 
5| `security_content_ctime(firstTime)` 
6| `security_content_ctime(lastTime)` 
7| `github_enterprise_disable_audit_log_event_stream_filter`

Data Source

Name Platform Sourcetype Source
GitHub Enterprise Audit Logs N/A 'httpevent' 'http:github'

Macros Used

Name Value
github_enterprise source=http:github sourcetype=httpevent
github_enterprise_disable_audit_log_event_stream_filter search *
github_enterprise_disable_audit_log_event_stream_filter is an empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.

Annotations

- MITRE ATT&CK
+ Kill Chain Phases
+ NIST
+ CIS
- Threat Actors
ID Technique Tactic
T1562.008 Disable or Modify Cloud Logs Defense Evasion
T1195 Supply Chain Compromise Initial Access
Delivery
Exploitation
DE.AE
CIS 13

Default Configuration

This detection is configured by default in Splunk Enterprise Security to run with the following settings:

Setting Value
Disabled true
Cron Schedule 0 * * * *
Earliest Time -70m@m
Latest Time -10m@m
Schedule Window auto
Creates Risk Event True
This configuration file applies to all detections of type anomaly. These detections will use Risk Based Alerting.

Implementation

You must ingest GitHub Enterprise logs using Audit log streaming as described in this documentation https://docs.github.com/en/enterprise-cloud@latest/admin/monitoring-activity-in-your-enterprise/reviewing-audit-logs-for-your-enterprise/streaming-the-audit-log-for-your-enterprise#setting-up-streaming-to-splunk using a Splunk HTTP Event Collector.

Known False Positives

unknown

Associated Analytic Story

Risk Based Analytics (RBA)

Risk Message:

Audit log event streaming is disabled by $user$

Risk Object Risk Object Type Risk Score Threat Objects
user user 25 user_agent

References

Detection Testing

Test Type Status Dataset Source Sourcetype
Validation ✅ Passing N/A N/A N/A
Unit ✅ Passing Dataset http:github httpevent
Integration ✅ Passing Dataset http:github httpevent

Replay any dataset to Splunk Enterprise by using our replay.py tool or the UI. Alternatively you can replay a dataset into a Splunk Attack Range

Source: GitHub | Version: 1