Detection: Disable Show Hidden Files

Updated Date: 2024-11-14 ID: 6f3ccfa2-91fe-11eb-8f9b-acde48001122 Author: Teoderick Contreras, Splunk, Steven Dick Type: Anomaly Product: Splunk Enterprise Security

Description

The following analytic detects modifications to the Windows registry that disable the display of hidden files. It leverages data from the Endpoint.Registry data model, specifically monitoring changes to registry paths associated with hidden file settings. This activity is significant because malware, such as worms and trojan spyware, often use hidden files to evade detection. If confirmed malicious, this behavior could allow an attacker to conceal malicious files on the system, making it harder for security tools and analysts to identify and remove the threat.

1
2| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime FROM datamodel=Endpoint.Registry WHERE (Registry.registry_path= "*\\SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Explorer\\Advanced\\Hidden" OR (Registry.registry_path= "*\\SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Explorer\\Advanced\\HideFileExt" Registry.registry_value_data = "0x00000001") OR (Registry.registry_path= "*\\SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Explorer\\Advanced\\ShowSuperHidden" Registry.registry_value_data = "0x00000000" )) BY Registry.user Registry.dest Registry.registry_path Registry.registry_key_name Registry.registry_value_name Registry.registry_value_data Registry.process_guid 
3| `drop_dm_object_name(Registry)` 
4| where isnotnull(registry_value_data) 
5| `security_content_ctime(firstTime)` 
6| `security_content_ctime(lastTime)` 
7| `disable_show_hidden_files_filter`

Data Source

Name Platform Sourcetype Source
Sysmon EventID 12 Windows icon Windows 'xmlwineventlog' 'XmlWinEventLog:Microsoft-Windows-Sysmon/Operational'
Sysmon EventID 13 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($field$)
disable_show_hidden_files_filter search *
disable_show_hidden_files_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
T1564.001 Hidden Files and Directories Defense Evasion
T1562.001 Disable or Modify Tools Defense Evasion
T1564 Hide Artifacts Defense Evasion
T1562 Impair Defenses Defense Evasion
T1112 Modify Registry Defense Evasion
KillChainPhase.EXPLOITAITON
NistCategory.DE_AE
Cis18Value.CIS_10
APT28
APT32
FIN13
HAFNIUM
Lazarus Group
LuminousMoth
Mustang Panda
RedCurl
Rocke
Transparent Tribe
Tropic Trooper
Agrius
Aquatic Panda
BRONZE BUTLER
Ember Bear
FIN6
Gamaredon Group
Gorgon Group
INC Ransom
Indrik Spider
Kimsuky
Lazarus Group
Magic Hound
MuddyWater
Play
Putter Panda
Rocke
Saint Bear
TA2541
TA505
TeamTNT
Turla
Wizard Spider
Magic Hound
APT19
APT32
APT38
APT41
Aquatic Panda
Blue Mockingbird
Dragonfly
Earth Lusca
Ember Bear
FIN8
Gamaredon Group
Gorgon Group
Indrik Spider
Kimsuky
LuminousMoth
Magic Hound
Patchwork
Saint Bear
Silence
TA505
Threat Group-3390
Turla
Volt Typhoon
Wizard Spider

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 need to be ingesting logs with the registry value name, registry path, and registry value data from your endpoints. If you are using Sysmon, you must have at least version 2.0 of the offical Sysmon TA. https://splunkbase.splunk.com/app/5709

Known False Positives

unknown

Associated Analytic Story

Risk Based Analytics (RBA)

Risk Message Risk Score Impact Confidence
Disabled 'Show Hidden Files' on $dest$ 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 WinEventLog:Security WinEventLog
Integration ✅ Passing Dataset WinEventLog:Security WinEventLog

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: 8