Detection: Suspicious Process DNS Query Known Abuse Web Services

Updated Date: 2025-02-10 ID: 3cf0dc36-484d-11ec-a6bc-acde48001122 Author: Teoderick Contreras, Splunk Type: TTP Product: Splunk Enterprise Security

Description

The following analytic detects a suspicious process making DNS queries to known, abused text-paste web services, VoIP, instant messaging, and digital distribution platforms. It leverages Sysmon EventID 22 logs to identify queries from processes like cmd.exe, powershell.exe, and others. This activity is significant as it may indicate an attempt to download malicious files, a common initial access technique. If confirmed malicious, this could lead to unauthorized code execution, data exfiltration, or further compromise of the target host.

Search

1`sysmon` EventCode=22 QueryName IN ("*pastebin*", "*discord*", "*api.telegram*","*t.me*") process_name IN ("cmd.exe", "*powershell*", "pwsh.exe", "wscript.exe","cscript.exe") OR Image IN ("*\\users\\public\\*", "*\\programdata\\*", "*\\temp\\*", "*\\Windows\\Tasks\\*", "*\\appdata\\*", "*\\perflogs\\*") 
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_dns_query_known_abuse_web_services_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_dns_query_known_abuse_web_services_filter	`search *`

suspicious_process_dns_query_known_abuse_web_services_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

Installation

DE.CM

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 Notable	Yes
Rule Title	`%name%`
Rule Description	`%description%`
Notable Event Fields	user, dest
Creates Risk Event	True

This configuration file applies to all detections of type TTP. These detections will use Risk Based Alerting and generate Notable Events.

Implementation

This detection relies on sysmon logs with the Event ID 22, DNS Query. We suggest you run this detection at least once a day over the last 14 days.

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:

Suspicious process $process_name$ made a DNS query for $QueryName$ on $dest$

Risk Object	Risk Object Type	Risk Score	Threat Objects
dest	system	64	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: 9