Detection: Windows Query Registry Browser List Application

Updated Date: 2024-05-28 ID: 45ebd21c-f4bf-4ced-bd49-d25b6526cebb Author: Teoderick Contreras, Splunk Type: Anomaly Product: Splunk Enterprise Security

Description

The following analytic detects a suspicious process accessing the registry entries for default internet browsers. It leverages Windows Security Event logs, specifically event code 4663, to identify access attempts to these registry paths. This activity is significant because adversaries can exploit this registry key to gather information about installed browsers and their settings, potentially leading to the theft of sensitive data such as login credentials and browsing history. If confirmed malicious, this behavior could enable attackers to exfiltrate sensitive information and compromise user accounts.

1`wineventlog_security` EventCode=4663 object_file_path IN ("*\\SOFTWARE\\Clients\\StartMenuInternet\\*", "*\\SOFTWARE\\Clients\\StartMenuInternet\\*") AND NOT (process_path IN ("*:\\Windows\\System32\\*", "*:\\Windows\\SysWow64\\*", "*:\\Program Files*", "*:\\Windows\\*")) 
2| stats count min(_time) as firstTime max(_time) as lastTime by object_file_name object_file_path process_name process_path  process_id EventCode dest 
3| `security_content_ctime(firstTime)` 
4| `security_content_ctime(lastTime)` 
5| `windows_query_registry_browser_list_application_filter`

Data Source

Name Platform Sourcetype Source Supported App
Windows Event Log Security 4663 Windows icon Windows 'xmlwineventlog' 'XmlWinEventLog:Security' N/A

Macros Used

Name Value
security_content_ctime convert timeformat="%Y-%m-%dT%H:%M:%S" ctime($field$)
windows_query_registry_browser_list_application_filter search *
windows_query_registry_browser_list_application_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
T1012 Query Registry Discovery
KillChainPhase.EXPLOITAITON
NistCategory.DE_AE
Cis18Value.CIS_10
APT32
APT39
APT41
Chimera
Dragonfly
Fox Kitten
Kimsuky
Lazarus Group
OilRig
Stealth Falcon
Threat Group-3390
Turla
Volt Typhoon
ZIRCONIUM

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
This configuration file applies to all detections of type anomaly. These detections will use Risk Based Alerting.

Implementation

To successfully implement this search, you must ingest Windows Security Event logs and track event code 4663. For 4663, enable "Audit Object Access" in Group Policy. Then check the two boxes listed for both "Success" and "Failure."

Known False Positives

uninstall application may access this registry to remove the entry of the target application. filter is needed.

Associated Analytic Story

Risk Based Analytics (RBA)

Risk Message Risk Score Impact Confidence
A suspicious process accessing installed default browser registry on $dest$ 25 50 50
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:Security XmlWinEventLog
Integration ✅ Passing Dataset XmlWinEventLog:Security 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: 2