Detection: Windows Credentials from Password Stores Chrome Extension Access

Updated Date: 2024-09-30 ID: 2e65afe0-9a75-4487-bd87-ada9a9f1b9af Author: Teoderick Contreras, Splunk Type: Anomaly Product: Splunk Enterprise Security

Description

The following analytic detects non-Chrome processes attempting to access the Chrome extensions file. It leverages Windows Security Event logs, specifically event code 4663, to identify this behavior. This activity is significant because adversaries may exploit this file to extract sensitive information from the Chrome browser, posing a security risk. If confirmed malicious, this could lead to unauthorized access to stored credentials and other sensitive data, potentially compromising the security of the affected system and broader network.

Search

1`wineventlog_security` EventCode=4663 object_file_path="*\\AppData\\Local\\Google\\Chrome\\User Data\\Default\\Local Extension Settings\\*" AND NOT (process_path IN ("*:\\Windows\\explorer.exe", "*\\chrome.exe")) 
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_credentials_from_password_stores_chrome_extension_access_filter`

Data Source

Name	Platform	Sourcetype	Source
Windows Event Log Security 4663	Windows	`'xmlwineventlog'`	`'XmlWinEventLog:Security'`

Macros Used

Name	Value
security_content_ctime	`convert timeformat="%Y-%m-%dT%H:%M:%S" ctime($field$)`
windows_credentials_from_password_stores_chrome_extension_access_filter	`search *`

windows_credentials_from_password_stores_chrome_extension_access_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

Daggerfly

Dragonfly

Fox Kitten

Indrik Spider

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 chrome browser extension application may access this file and folder path to removed chrome installation in the target host. Filter is needed.

Associated Analytic Story

Risk Based Analytics (RBA)

Risk Message	Risk Score	Impact	Confidence
A non-chrome process $process_name$ accessing chrome browser extension folder files 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

https://malpedia.caad.fkie.fraunhofer.de/details/win.redline_stealer

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: 3