Detection: Wermgr Process Connecting To IP Check Web Services

Updated Date: 2024-09-30 ID: ed313326-a0f9-11eb-a89c-acde48001122 Author: Teoderick Contreras, Mauricio Velazco, Splunk Type: TTP Product: Splunk Enterprise Security

Description

The following analytic detects the wermgr.exe process attempting to connect to known IP check web services. It leverages Sysmon EventCode 22 to identify DNS queries made by wermgr.exe to specific IP check services. This activity is significant because wermgr.exe is typically used for Windows error reporting, and its connection to these services may indicate malicious code injection, often associated with malware like Trickbot. If confirmed malicious, this behavior could allow attackers to recon the infected machine's IP address, aiding in further exploitation and evasion tactics.

Search

1`sysmon` EventCode =22 process_name = wermgr.exe QueryName IN ("*wtfismyip.com", "*checkip.amazonaws.com", "*ipecho.net", "*ipinfo.io", "*api.ipify.org", "*icanhazip.com", "*ip.anysrc.com","*api.ip.sb", "ident.me", "www.myexternalip.com", "*zen.spamhaus.org", "*cbl.abuseat.org", "*b.barracudacentral.org","*dnsbl-1.uceprotect.net", "*spam.dnsbl.sorbs.net") 
2|  stats  min(_time) as firstTime max(_time) as lastTime count by Image process_name ProcessId QueryName QueryStatus QueryResults EventCode Computer 
3| rename Computer as dest 
4| `security_content_ctime(firstTime)` 
5| `security_content_ctime(lastTime)` 
6| `wermgr_process_connecting_to_ip_check_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($field$)`
wermgr_process_connecting_to_ip_check_web_services_filter	`search *`

wermgr_process_connecting_to_ip_check_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
T1590	Gather Victim Network Information	Reconnaissance
T1590.005	IP Addresses	Reconnaissance

KillChainPhase.RECONNAISSANCE

NistCategory.DE_CM

Cis18Value.CIS_10

HAFNIUM

Indrik Spider

Volt Typhoon

Andariel

HAFNIUM

Magic Hound

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

To successfully implement this search, you need to be ingesting logs with the process name, dns query name process path , and query ststus from your endpoints like EventCode 22. If you are using Sysmon, you must have at least version 12 of the Sysmon TA.

Known False Positives

unknown

Associated Analytic Story

Trickbot

Risk Based Analytics (RBA)

Risk Message	Risk Score	Impact	Confidence
Wermgr.exe process connecting IP location web services on $dest$	56	70	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: 4