Alerting

Splunk Alert creation for 5 Unsuccessful Login attempt from same source and same destination?

rajuljain_mc
New Member

Sample log-
Cisco ACS Authentication Failed
Nov 3 08:21:13 REL-DC-MSTCRD-ACS CSCOacs_Failed_Attempts 0001982755 2 0 2017-11-03 08:21:13.484 +05:30 0038659009 5401 NOTICE Failed-Attempt:
Authentication failed, ACSVersion=acs-5.8.1.4-B.462.x86_64, ConfigVersionId=53, Device IP Address=10.150.0.5, Device Port=44041,
DestinationIPAddress=172.20.1.200, DestinationPort=49, UserName=mvparam, Protocol=Tacacs, RequestLatency=141, Type=Authentication, Action=Login,
Privilege-Level=15, Authen-Type=ASCII, Service=Enable, User=rajul, Port=39, Remote-Address=172.20.1.152, UserName=rajul,
AcsSessionID=REL-DC-MSTCRD-ACS/278522990/2009452, AuthenticationIdentityStore=Internal Users, AuthenticationMethod=PAP_ASCII,
SelectedAccessService=IMC-Access, IdentityGroup=IdentityGroup:All Groups:IMC-L2G, FailureReason=22004 , Step=13013 , Step=15008 , Step=15004 ,
Step=15012 , Step=15041 , Step=15006 , Step=15013 , Step=24210 , Step=24212 , Step=13045 , Step=13015 , Step=13014 , Step=15037 , Step=15041 ,
Step=15006 , Step=15013 , Step=24210 , Step=24212 , Step=22004

Query-index=ecs_legacy source="/var/log/cisco-acs.log" "NOTICE Failed-Attempt: Authentication failed"

Stuck after this query, help to write rule please?

0 Karma

hardikJsheth
Motivator

In case you want to take time in consideration as well to check for consecutive unsuccessful login attempts, either you can use timechar command or add bin command to the query as follows:

index=ecs_legacy source="/var/log/cisco-acs.log" "NOTICE Failed-Attempt: Authentication failed" | bin _time span=5m| stats count by DestinationIPAddress, Remote-Address, UserName | where count > 5
0 Karma

harsmarvania57
Ultra Champion

Hi

Can you please try this query ?

index=ecs_legacy source="/var/log/cisco-acs.log" "NOTICE Failed-Attempt: Authentication failed" | stats count by DestinationIPAddress, Remote-Address, UserName | where count > 5

EDIT: Or may be below query because I don't know which is your source and destination IPs, you can change your source and destionation IP field in given query.

    index=ecs_legacy source="/var/log/cisco-acs.log" "NOTICE Failed-Attempt: Authentication failed" | stats count by DestinationIPAddress, "Device IP Address", UserName | where count > 5

Thanks,
Harshil

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!

Cisco Data Fabric from Architecture to Investigation, Better SOC Visibility, and More ...

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

The Trust Gap: Why a Data Foundation is Fundamental to an Agentic Enterprise

The Trust Gap: Why a data foundation is fundamental to an  Agentic Enterprise.   Agentic AI is transforming ...

Data Management Digest – September 2026

    Welcome to the September 2026 edition of Data Management Digest! September brought a fresh wave of ...