ID | Technique | Tactic |
---|---|---|
T1586 | Compromise Accounts | Resource Development |
T1586.003 | Cloud Accounts | Resource Development |
T1556 | Modify Authentication Process | Credential Access |
T1556.006 | Multi-Factor Authentication | Defense Evasion |
Detection: GCP Multi-Factor Authentication Disabled
Description
The following analytic detects an attempt to disable multi-factor authentication (MFA) for a Google Cloud Platform (GCP) user. It leverages Google Workspace Admin log events, specifically the UNENROLL_USER_FROM_STRONG_AUTH
command. This activity is significant because disabling MFA can allow an adversary to maintain persistence within the environment using a compromised account without raising suspicion. If confirmed malicious, this action could enable attackers to bypass additional security layers, potentially leading to unauthorized access, data exfiltration, or further exploitation of the compromised account.
Search
1`gws_reports_admin` command=UNENROLL_USER_FROM_STRONG_AUTH
2| stats count min(_time) as firstTime max(_time) as lastTime by user, command, actor.email, status, id.applicationName, event.name, vendor_account, action
3| `security_content_ctime(firstTime)`
4| `security_content_ctime(lastTime)`
5| `gcp_multi_factor_authentication_disabled_filter`
Data Source
Name | Platform | Sourcetype | Source | Supported App |
---|---|---|---|---|
N/A | N/A | N/A | N/A | N/A |
Macros Used
Name | Value |
---|---|
gws_reports_admin | sourcetype=gws:reports:admin |
gcp_multi_factor_authentication_disabled_filter | search * |
gcp_multi_factor_authentication_disabled_filter
is an empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.
Annotations
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 Notable | Yes |
Rule Title | %name% |
Rule Description | %description% |
Notable Event Fields | user, dest |
Creates Risk Event | True |
Implementation
You must install the latest version of Splunk Add-on for Google Workspace from Splunkbase (https://splunkbase.splunk.com/app/5556) which allows Splunk administrators to collect Google Workspace event data in Splunk using Google Workspace APIs. Specifically, this analytic leverages the Admin log events.
Known False Positives
Legitimate use case may require for users to disable MFA. Filter as needed.
Associated Analytic Story
Risk Based Analytics (RBA)
Risk Message | Risk Score | Impact | Confidence |
---|---|---|---|
MFA disabled for User $user$ initiated by $actor.email$ | 45 | 50 | 90 |
References
Detection Testing
Test Type | Status | Dataset | Source | Sourcetype |
---|---|---|---|---|
Validation | ✅ Passing | N/A | N/A | N/A |
Unit | ✅ Passing | Dataset | gws:reports:admin |
gws:reports:admin |
Integration | ✅ Passing | Dataset | gws:reports:admin |
gws:reports:admin |
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: 3