Splunk Search

Removing events with duplicate fields from transaction command

dineshp
Explorer

Hi all,
I am writing a query to detect brute force attempts, where the username is different in each request.
index=syslog username!="NULL" | transaction clientip maxspan=60m maxpause=2m | stats count by clientip | search count >5 | sort count desc

This is giving me if someone has typed in same username within 2 mins, i want to avoid those. So i want to know if someone tried to login more than 5 times with different usernames from the same IP.

I tried my luck with dedup, but it doesn't seem to be working.
index=syslog username!="NULL" | transaction clientip maxspan=60m maxpause=2m | dedup username | stats count by clientip | search count >5 | sort count desc

Thank You

0 Karma

mydog8it
Builder

Pretty sure this will do what you want...

index=syslog username!="NULL" | transaction clientip maxspan=60m maxpause=2m | stats dc(clientip) AS "Client IP" values(username) AS "User Name" dc(username) AS "usernames" by clientip | where usernames > 5 | table clientip, "User Name"

0 Karma

knielsen
Contributor

Hi,

I don't have logfiles to recreate your scenario, so I can't test this, but would this work?

index=syslog username!="NULL" | transaction clientip maxspan=60m maxpause=2m | stats count as ipcount dc(username) as usercount by clientip | where ipcount>5 AND usercount>5

That would only catch cases where each login was tried with a different username though, perhaps usercount>3 or something would be nice.

Hth,
Kai.

0 Karma
Got questions? Get answers!

Join the Splunk Community Slack to learn, troubleshoot, and make connections with fellow Splunk practitioners in real time!

Meet up IRL or virtually!

Join Splunk User Groups to connect and learn in-person by region or remotely by topic or industry.

Get Updates on the Splunk Community!

Get Agentic with Splunk Lantern: Connect to Cisco Cloud Control, Transform ...

Splunk Lantern is Splunk’s customer success center that provides practical guidance from Splunk experts on key ...

July Community Events: Master ITSI 5.0 & Automate Splunk

Struggling with alert fatigue or feeling like you're spending more time on infrastructure maintenance than ...

New Release of Federated Search: Bringing Splunk Analytics to More of Your Data

Organizations today are generating more data than ever and storing it across cloud object stores, data lakes, ...