Detection: Detect Remote Access Software Usage FileInfo

Updated Date: 2024-11-13 ID: ccad96d7-a48c-4f13-8b9c-9f6a31cba454 Author: Steven Dick Type: Anomaly Product: Splunk Enterprise Security

Description

The following analytic detects the execution of processes with file or code signing attributes from known remote access software within the environment. It leverages Sysmon EventCode 1 data and cross-references a lookup table of remote access utilities such as AnyDesk, GoToMyPC, LogMeIn, and TeamViewer. This activity is significant as adversaries often use these tools to maintain unauthorized remote access. If confirmed malicious, this could allow attackers to persist in the environment, potentially leading to data exfiltration or further compromise of the network.

1`sysmon` EventCode=1 
2| stats count min(_time) as firstTime max(_time) as lastTime, values(Company) as Company values(Product) as Product by dest, user, parent_process_name, process_name, process 
3| lookup remote_access_software remote_utility_fileinfo AS Product OUTPUT isutility, description as signature, comment_reference as desc, category 
4| search isutility = True 
5| `remote_access_software_usage_exceptions` 
6| `detect_remote_access_software_usage_fileinfo_filter`

Data Source

Name Platform Sourcetype Source
CrowdStrike ProcessRollup2 N/A 'crowdstrike:events:sensor' 'crowdstrike'
Sysmon EventID 1 Windows icon Windows 'xmlwineventlog' 'XmlWinEventLog:Microsoft-Windows-Sysmon/Operational'
Windows Event Log Security 4688 Windows icon Windows 'xmlwineventlog' 'XmlWinEventLog:Security'

Macros Used

Name Value
remote_access_software_usage_exceptions `eval exception_asset = CASE(isnotnull(src),src,isnotnull(dest),dest)
detect_remote_access_software_usage_fileinfo_filter search *
detect_remote_access_software_usage_fileinfo_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
T1219 Remote Access Software Command And Control
Command and Control
DE.AE
CIS 10

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

This analytic relies on Sysmon to be properly installed and utilized in the environment. Ensure that proper logging is setup for Sysmon and data is being ingested into Splunk. The "exceptions" macro leverages both an Assets and Identities lookup, as well as a KVStore collection named "remote_software_exceptions" that lets you track and maintain device-based exceptions for this set of detections.

Known False Positives

Known or approved applications used by the organization or usage of built-in functions. Known false positives can be added to the remote_access_software_usage_exception.csv lookup to globally suppress these situations across all remote access content

Associated Analytic Story

Risk Based Analytics (RBA)

Risk Message:

A file attributes for known a remote access software [$process_name$] was detected on $dest$

Risk Object Risk Object Type Risk Score Threat Objects
dest system 25 process_name

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: 5