| ID | Technique | Tactic |
|---|---|---|
| T1195.002 | Compromise Software Supply Chain | Initial Access |
| T1195 | Supply Chain Compromise | Initial Access |
Detection: GitHub Actions Disable Security Workflow
Description
The following analytic detects the disabling of a security workflow in GitHub Actions. It leverages GitHub logs to identify when a workflow, excluding those named security-testing, is disabled following a push or pull request event. This activity is significant as it may indicate an attempt by an attacker to conceal malicious code by disabling security checks. If confirmed malicious, this could allow the attacker to introduce and persist undetected malicious code within the repository, potentially compromising the integrity and security of the codebase.
Search
1`github` workflow_run.event=push OR workflow_run.event=pull_request
2| stats values(workflow_run.name) as workflow_run.name by workflow_run.head_commit.id workflow_run.event workflow_run.head_branch workflow_run.head_commit.author.email workflow_run.head_commit.author.name workflow_run.head_commit.message workflow_run.head_commit.timestamp workflow_run.head_repository.full_name workflow_run.head_repository.owner.id workflow_run.head_repository.owner.login workflow_run.head_repository.owner.type
3| rename workflow_run.head_commit.author.name as user, workflow_run.head_commit.author.email as user_email, workflow_run.head_repository.full_name as repository, workflow_run.head_branch as branch
4| search NOT workflow_run.name=*security-testing*
5| `security_content_ctime(firstTime)`
6| `security_content_ctime(lastTime)`
7| `github_actions_disable_security_workflow_filter`
Data Source
| Name | Platform | Sourcetype | Source | Supported App |
|---|---|---|---|---|
| GitHub |  AWS |
'aws:firehose:json' |
'github' |
N/A |
Macros Used
| Name | Value |
|---|---|
| github | sourcetype=aws:firehose:json |
| github_actions_disable_security_workflow_filter | search * |
github_actions_disable_security_workflow_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
KillChainPhase.DELIVERY
NistCategory.DE_AE
Cis18Value.CIS_13
APT41
Cobalt Group
Dragonfly
FIN7
GOLD SOUTHFIELD
Sandworm Team
Threat Group-3390
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 index GitHub logs. You can follow the url in reference to onboard GitHub logs. Sometimes GitHub logs are truncated, make sure to disable it in props.conf. Replace security-testing with the name of your security testing workflow in GitHub Actions.
Known False Positives
unknown
Associated Analytic Story
Risk Based Analytics (RBA)
| Risk Message | Risk Score | Impact | Confidence |
|---|---|---|---|
| Security Workflow is disabled in branch $branch$ for repository $repository$ | 27 | 30 | 90 |
The Risk Score is calculated by the following formula: Risk Score = (Impact * Confidence/100). Initial Confidence and Impact is set by the analytic author.
References
Detection Testing
| Test Type | Status | Dataset | Source | Sourcetype |
|---|---|---|---|---|
| Validation | ✅ Passing | N/A | N/A | N/A |
| Unit | ✅ Passing | Dataset | github |
aws:firehose:json |
| Integration | ✅ Passing | Dataset | github |
aws:firehose:json |
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: 2