Detection: Windows Gather Victim Identity SAM Info

Description

The following analytic detects processes loading the samlib.dll or samcli.dll modules, which are often abused to access Security Account Manager (SAM) objects or credentials on domain controllers. This detection leverages Sysmon EventCode 7 to identify these DLLs being loaded outside typical system directories. Monitoring this activity is crucial as it may indicate attempts to gather sensitive identity information. If confirmed malicious, this behavior could allow attackers to obtain credentials, escalate privileges, or further infiltrate the network.

1`sysmon` EventCode=7  (ImageLoaded = "*\\samlib.dll" AND OriginalFileName = "samlib.dll") OR (ImageLoaded = "*\\samcli.dll" AND OriginalFileName = "SAMCLI.DLL") AND NOT (Image IN("C:\\Windows\\*", "C:\\Program File*", "%systemroot%\\*")) 
2| stats count min(_time) as firstTime max(_time) as lastTime by Image ImageLoaded process_name dest EventCode Signed ProcessId 
3| `security_content_ctime(firstTime)` 
4| `security_content_ctime(lastTime)` 
5| `windows_gather_victim_identity_sam_info_filter`

Data Source

Name Platform Sourcetype Source
Sysmon EventID 7 Windows icon Windows 'xmlwineventlog' 'XmlWinEventLog:Microsoft-Windows-Sysmon/Operational'

Macros Used

Name Value
security_content_ctime convert timeformat="%Y-%m-%dT%H:%M:%S" ctime($field$)
windows_gather_victim_identity_sam_info_filter search *
windows_gather_victim_identity_sam_info_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
ID Technique Tactic
T1589.001 Credentials Reconnaissance
T1589 Gather Victim Identity Information Reconnaissance
KillChainPhase.RECONNAISSANCE
NistCategory.DE_AE
Cis18Value.CIS_10
APT28
Chimera
LAPSUS$
Leviathan
Magic Hound
APT32
FIN13
HEXANE
LAPSUS$
Magic Hound
Star Blizzard
Volt Typhoon

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 False
This configuration file applies to all detections of type hunting.

Implementation

The latest Sysmon TA 3.0 https://splunkbase.splunk.com/app/5709 will add the ImageLoaded name to the process_name field, allowing this query to work. Use as an example and implement for other products.

Known False Positives

this module can be loaded by a third party application. Filter is needed.

Associated Analytic Story

Risk Based Analytics (RBA)

Risk Message Risk Score Impact Confidence
An instance of $dest$ that loads $ImageLoaded$ that are related to accessing to SAM object information. 9 30 30
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 XmlWinEventLog:Microsoft-Windows-Sysmon/Operational XmlWinEventLog
Integration ✅ Passing Dataset XmlWinEventLog:Microsoft-Windows-Sysmon/Operational XmlWinEventLog

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