| ID | Technique | Tactic |
|---|---|---|
| T1566 | Phishing | Initial Access |
| T1566.001 | Spearphishing Attachment | Initial Access |
Detection: O365 Safe Links Detection
Description
The following analytic detects when any Microsoft Safe Links alerting is triggered. This behavior may indicate when user has interacted with a phishing or otherwise malicious link within the Microsoft Office ecosystem.
Search
1`o365_management_activity` Name="*a potentially malicious URL*" Operation=AlertEntityGenerated
2| fromjson Data
3| stats count min(_time) as firstTime max(_time) as lastTime values(ObjectId) as url values(od) as desc by AlertId,trc,Operation,Name,ot
4| rename Name as signature, AlertId as signature_id, trc as user,ot as action
5| eval action = CASE(action == "Allowed", "allowed", action=="BlockPageOverride", "allowed", true(),"blocked")
6| `security_content_ctime(firstTime)`
7| `security_content_ctime(lastTime)`
8| `o365_safe_links_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_safe_links_detection_filter | search * |
o365_safe_links_detection_filter is an empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.
Annotations
MITRE ATT&CK
Kill Chain Phases
NIST
CIS
Threat Actors
KillChainPhase.DELIVERY
NistCategory.DE_CM
Cis18Value.CIS_10
Axiom
GOLD SOUTHFIELD
APT-C-36
APT1
APT12
APT19
APT28
APT29
APT30
APT32
APT33
APT37
APT38
APT39
APT41
Ajax Security Team
Andariel
BITTER
BRONZE BUTLER
BlackTech
Cobalt Group
Confucius
DarkHydrus
Darkhotel
Dragonfly
EXOTIC LILY
Elderwood
Ember Bear
FIN4
FIN6
FIN7
FIN8
Ferocious Kitten
Gallmaker
Gamaredon Group
Gorgon Group
Higaisa
Inception
IndigoZebra
Kimsuky
Lazarus Group
LazyScripter
Leviathan
Machete
Malteiro
Mofang
Molerats
MuddyWater
Mustang Panda
Naikon
Nomadic Octopus
OilRig
PLATINUM
Patchwork
RTM
Rancor
Sandworm Team
SideCopy
Sidewinder
Silence
TA2541
TA459
TA505
TA551
The White Company
Threat Group-3390
Tonto Team
Transparent Tribe
Tropic Trooper
WIRTE
Windshift
Wizard Spider
admin@338
menuPass
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 |
This configuration file applies to all detections of type TTP. These detections will use Risk Based Alerting and generate Notable Events.
Implementation
You must install the Splunk Microsoft Office 365 Add-on and ingest Office 365 management activity events. The Safe Links capability must be configured and is typically only available to E3/E5 level customers.
Known False Positives
Based on Safe Links policies, may vary.
Associated Analytic Story
Risk Based Analytics (RBA)
| Risk Message | Risk Score | Impact | Confidence |
|---|---|---|---|
| $user$ triggered a Microsoft Safe Links detection. | 40 | 40 | 100 |
The Risk Score is calculated by the following formula: Risk Score = (Impact * Confidence/100). Initial Confidence and Impact is set by the analytic author.
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