ID | Technique | Tactic |
---|---|---|
T1566 | Phishing | Initial Access |
T1566.001 | Spearphishing Attachment | Initial Access |
T1566.002 | Spearphishing Link | Initial Access |
Detection: O365 ZAP Activity Detection
Description
The following analytic detects when the Microsoft Zero-hour Automatic Purge (ZAP) capability takes action against a user's mailbox. This capability is an enhanced protection feature that retro-actively removes email with known malicious content for user inboxes. Since this is a retroactive capability, there is still a window in which the user may fall victim to the malicious content.
Search
1`o365_management_activity` Workload=SecurityComplianceCenter Operation=AlertEntityGenerated Name="*messages containing malicious*"
2| fromjson Data
3| stats count min(_time) as firstTime max(_time) as lastTime values(zu) as url values(zfn) as file_name values(ms) as subject values(ttr) as result values(tsd) as src_user by AlertId,trc,Operation,Name
4| rename Name as signature, AlertId as signature_id, trc as user
5| eval action = CASE(match(result,"Success"), "blocked", true(),"allowed"), url = split(url,";")
6| `security_content_ctime(firstTime)`
7| `security_content_ctime(lastTime)`
8| `o365_zap_activity_detection_filter`
Data Source
Name | Platform | Sourcetype | Source | Supported App |
---|---|---|---|---|
N/A | N/A | N/A | N/A | N/A |
Macros Used
Name | Value |
---|---|
o365_management_activity | sourcetype=o365:management:activity |
o365_zap_activity_detection_filter | search * |
o365_zap_activity_detection_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 Splunk Microsoft Office 365 Add-on and ingest Office 365 management activity events. Some features of Zero-hour purge are only offered within E3/E5 license level tenants, events may not be available otherwise.
Known False Positives
unknown
Associated Analytic Story
Risk Based Analytics (RBA)
Risk Message | Risk Score | Impact | Confidence |
---|---|---|---|
User $user$ was included in a ZAP protection activity. | 10 | 20 | 50 |
References
Detection Testing
Test Type | Status | Dataset | Source | Sourcetype |
---|---|---|---|---|
Validation | ✅ Passing | N/A | N/A | N/A |
Unit | ✅ Passing | Dataset | o365 |
o365:management:activity |
Integration | ✅ Passing | Dataset | o365 |
o365:management:activity |
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: 1