ID | Technique | Tactic |
---|---|---|
T1526 | Cloud Service Discovery | Discovery |
Detection: ASL AWS Excessive Security Scanning
DEPRECATED DETECTION
This detection has been marked as deprecated by the Splunk Threat Research team. This means that it will no longer be maintained or supported. If you have any questions or concerns, please reach out to us at research@splunk.com.
Description
This search looks for AWS CloudTrail events and analyse the amount of eventNames which starts with Describe by a single user. This indicates that this user scans the configuration of your AWS cloud environment.
Search
1`amazon_security_lake` api.operation=Describe* OR api.operation=List* OR api.operation=Get*
2| stats dc(api.operation) as dc_api_operations min(_time) as firstTime max(_time) as lastTime values(http_request.user_agent) as http_request.user_agent values(src_endpoint.ip) as src_endpoint.ip values(cloud.region) as cloud.region values(identity.user.account_uid) as identity.user.account_uid by identity.user.name
3| where dc_api_operations > 50
4| `security_content_ctime(firstTime)`
5| `security_content_ctime(lastTime)`
6|`asl_aws_excessive_security_scanning_filter`
Data Source
Name | Platform | Sourcetype | Source | Supported App |
---|---|---|---|---|
N/A | N/A | N/A | N/A | N/A |
Macros Used
Name | Value |
---|---|
amazon_security_lake | sourcetype=aws:cloudtrail:lake |
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 Risk Event | True |
Implementation
You must install Splunk Add-On for AWS Version v7.0.0 (https://splunkbase.splunk.com/app/1876) that includes includes a merge of all the capabilities of the Splunk Add-on for Amazon Security Lake. This search works with Amazon Security Lake logs which are parsed in the Open Cybersecurity Schema Framework (OCSF)format.
Known False Positives
While this search has no known false positives.
Associated Analytic Story
Risk Based Analytics (RBA)
Risk Message | Risk Score | Impact | Confidence |
---|---|---|---|
user $identity.user.name$ has excessive number of api calls. | 18 | 30 | 60 |
References
Detection Testing
Test Type | Status | Dataset | Source | Sourcetype |
---|---|---|---|---|
Validation | Not Applicable | N/A | N/A | N/A |
Unit | ❌ Failing | N/A | N/A |
N/A |
Integration | ❌ Failing | N/A | N/A |
N/A |
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