Detection: Suspicious Process With Discord DNS Query

Updated Date: 2024-09-30 ID: 4d4332ae-792c-11ec-89c1-acde48001122 Author: Teoderick Contreras, Mauricio Velazco, Splunk Type: Anomaly Product: Splunk Enterprise Security

Description

The following analytic identifies a process making a DNS query to Discord, excluding legitimate Discord application paths. It leverages Sysmon logs with Event ID 22 to detect DNS queries containing "discord" in the QueryName field. This activity is significant because Discord can be abused by adversaries to host and download malicious files, as seen in the WhisperGate campaign. If confirmed malicious, this could indicate malware attempting to download additional payloads from Discord, potentially leading to further code execution and compromise of the affected system.

Search

1`sysmon` EventCode=22 QueryName IN ("*discord*") Image != "*\\AppData\\Local\\Discord\\*" AND Image != "*\\Program Files*" AND Image != "discord.exe" 
2| stats count min(_time) as firstTime max(_time) as lastTime by Image QueryName QueryStatus process_name QueryResults Computer 
3| rename Computer as dest 
4| `security_content_ctime(firstTime)` 
5| `security_content_ctime(lastTime)` 
6| `suspicious_process_with_discord_dns_query_filter`

Data Source

Name	Platform	Sourcetype	Source
Sysmon EventID 22	Windows	`'xmlwineventlog'`	`'XmlWinEventLog:Microsoft-Windows-Sysmon/Operational'`

Macros Used

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

suspicious_process_with_discord_dns_query_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
T1059.005	Visual Basic	Execution
T1059	Command and Scripting Interpreter	Execution

KillChainPhase.INSTALLATION

NistCategory.DE_AE

Cis18Value.CIS_10

APT-C-36

APT32

APT33

APT37

APT38

APT39

BRONZE BUTLER

Cobalt Group

Confucius

Earth Lusca

FIN13

FIN4

FIN7

Gamaredon Group

Gorgon Group

HEXANE

Higaisa

Inception

Kimsuky

Lazarus Group

LazyScripter

Leviathan

Machete

Magic Hound

Malteiro

Molerats

MuddyWater

Mustang Panda

OilRig

Patchwork

Rancor

RedCurl

Sandworm Team

SideCopy

Sidewinder

Silence

TA2541

TA459

TA505

Transparent Tribe

Turla

WIRTE

Windshift

APT19

APT32

APT37

APT39

Dragonfly

FIN5

FIN6

FIN7

Fox Kitten

Ke3chang

OilRig

Saint Bear

Stealth Falcon

Whitefly

Windigo

Winter Vivern

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

his detection relies on sysmon logs with the Event ID 22, DNS Query.

Known False Positives

Noise and false positive can be seen if the following instant messaging is allowed to use within corporate network. In this case, a filter is needed.

Associated Analytic Story

Risk Based Analytics (RBA)

Risk Message	Risk Score	Impact	Confidence
suspicious process $process_name$ has a dns query in $QueryName$ on $dest$	64	80	80

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: 5