ID | Technique | Tactic |
---|---|---|
T1535 | Unused/Unsupported Cloud Regions | Defense Evasion |
Detection: AWS Cloud Provisioning From Previously Unseen City
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 provisioning activities from previously unseen cities. Provisioning activities are defined broadly as any event that begins with "Run" or "Create." This search is deprecated and have been translated to use the latest Change Datamodel.
Search
1`cloudtrail` (eventName=Run* OR eventName=Create*)
2| iplocation sourceIPAddress
3| search City=* [search `cloudtrail` (eventName=Run* OR eventName=Create*)
4| iplocation sourceIPAddress
5| search City=*
6| stats earliest(_time) as firstTime, latest(_time) as lastTime by sourceIPAddress, City, Region, Country
7| inputlookup append=t previously_seen_provisioning_activity_src.csv
8| stats min(firstTime) as firstTime max(lastTime) as lastTime by sourceIPAddress, City, Region, Country
9| outputlookup previously_seen_provisioning_activity_src.csv
10| stats min(firstTime) as firstTime max(lastTime) as lastTime by City
11| eval newCity=if(firstTime >= relative_time(now(), "-70m@m"), 1, 0)
12| where newCity=1
13| table City]
14| spath output=user userIdentity.arn
15| rename sourceIPAddress as src_ip
16| table _time, user, src_ip, City, eventName, errorCode
17| `aws_cloud_provisioning_from_previously_unseen_city_filter`
Data Source
Name | Platform | Sourcetype | Source | Supported App |
---|---|---|---|---|
N/A | N/A | N/A | N/A | N/A |
Macros Used
Name | Value |
---|---|
cloudtrail | sourcetype=aws:cloudtrail |
aws_cloud_provisioning_from_previously_unseen_city_filter | search * |
aws_cloud_provisioning_from_previously_unseen_city_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 Risk Event | True |
Implementation
You must install the AWS App for Splunk (version 5.1.0 or later) and Splunk Add-on for AWS (version 4.4.0 or later), then configure your AWS CloudTrail inputs. This search works best when you run the "Previously Seen AWS Provisioning Activity Sources" support search once to create a history of previously seen locations that have provisioned AWS resources.
Known False Positives
This is a strictly behavioral search, so we define "false positive" slightly differently. Every time this fires, it will accurately reflect the first occurrence in the time period you're searching within, plus what is stored in the cache feature. But while there are really no "false positives" in a traditional sense, there is definitely lots of noise. This search will fire any time a new city is seen in the GeoIP database for any kind of provisioning activity. If you typically do all provisioning from tools inside of your city, there should be few false positives. If you are located in countries where the free version of MaxMind GeoIP that ships by default with Splunk has weak resolution (particularly small countries in less economically powerful regions), this may be much less valuable to you.
Associated Analytic Story
Risk Based Analytics (RBA)
Risk Message | Risk Score | Impact | Confidence |
---|---|---|---|
tbd | 25 | 50 | 50 |
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: 3