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Description

This search looks for cloud provisioning activities from previously unseen cities. Provisioning activities are defined broadly as any event that runs or creates something.

Annotations

ATT&CK
ID Technique Tactic
T1078 Valid Accounts Defense Evasion, Initial Access, Persistence, Privilege Escalation
Kill Chain Phase
  • Actions on Objectives
NIST
  • ID.AM
CIS20
  • CIS 1
CVE
1
2
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| tstats earliest(_time) as firstTime, latest(_time) as lastTime from datamodel=Change where (All_Changes.action=started OR All_Changes.action=created) All_Changes.status=success by All_Changes.src, All_Changes.user, All_Changes.object, All_Changes.command 
| `drop_dm_object_name("All_Changes")` 
| iplocation src 
| where isnotnull(City) 
| lookup previously_seen_cloud_provisioning_activity_sources City as City OUTPUT firstTimeSeen, enough_data 
| eventstats max(enough_data) as enough_data 
| where enough_data=1 
| eval firstTimeSeenCity=min(firstTimeSeen) 
| where isnull(firstTimeSeenCity) OR firstTimeSeenCity > relative_time(now(), `previously_unseen_cloud_provisioning_activity_window`) 
| table firstTime, src, City, user, object, command 
| `cloud_provisioning_activity_from_previously_unseen_city_filter` 
| `security_content_ctime(firstTime)`

Macros

The SPL above uses the following Macros:

Note that cloud_provisioning_activity_from_previously_unseen_city_filter is a empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.

Lookups

The SPL above uses the following Lookups:

Required field

  • _time
  • All_Changes.action
  • All_Changes.status
  • All_Changes.src
  • All_Changes.user
  • All_Changes.object
  • All_Changes.command

How To Implement

You must be ingesting your cloud infrastructure logs from your cloud provider. You should run the baseline search Previously Seen Cloud Provisioning Activity Sources - Initial to build the initial table of source IP address, geographic locations, and times. You must also enable the second baseline search Previously Seen Cloud Provisioning Activity Sources - Update to keep this table up to date and to age out old data. You can adjust the time window for this search by updating the previously_unseen_cloud_provisioning_activity_window macro. You can also provide additional filtering for this search by customizing the cloud_provisioning_activity_from_previously_unseen_city_filter macro.

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 IP address is seen in the GeoIP database for any kind of provisioning activity. If you typically do all provisioning from tools inside of your country, 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

RBA

Risk Score Impact Confidence Message
18.0 30 60 User $user$ is starting or creating an instance $dest$ for the first time in City $City$ from IP address $src$

Reference

Test Dataset

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

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