Splunk Search

Is this the correct way to extract successful and failed logins from /var/log/secure in a search?

sureshsala
Explorer

I need help with the regular expression for field extraction of login status:

Successful:

source="/var/log/secure" | rex field=_raw " user (?[^ ]+)"| search user="*" | chart count BY host,user 

Failed:

source="/var/log/secure" | rex field=_raw " invalid user (?[^ ]+)"| search user="*" | chart count BY host,user 

Is this the right way to do it, or there is a better way?

Please help.

0 Karma
1 Solution

somesoni2
Revered Legend

Assuming your regex is correctly extracting the users, I would try like this (I would always throw the index and sourcetype as well)

Successfull

index=yourIndex sourcetype=yourSourcetype source="/var/log/secure" "session opened for user " | rex field=_raw "session opened for user (?<user>[^ ]+)"  | chart count BY host,user

Failed

index=yourIndex sourcetype=yourSourcetype  source="/var/log/secure" fail OR invalid | rex field=_raw " invalid user (?<user>[^ ]+)" | chart count BY host,user 

View solution in original post

somesoni2
Revered Legend

Assuming your regex is correctly extracting the users, I would try like this (I would always throw the index and sourcetype as well)

Successfull

index=yourIndex sourcetype=yourSourcetype source="/var/log/secure" "session opened for user " | rex field=_raw "session opened for user (?<user>[^ ]+)"  | chart count BY host,user

Failed

index=yourIndex sourcetype=yourSourcetype  source="/var/log/secure" fail OR invalid | rex field=_raw " invalid user (?<user>[^ ]+)" | chart count BY host,user 

sureshsala
Explorer

@somesoni2 Awesome, thanks a lot but failed regex is added NULL user and I am unable to figure out.

0 Karma

sureshsala
Explorer

Answer:

source="/var/log/secure" input_userauth_request AND (fail OR invalid) | rex field=_raw " invalid user (?[^ ]+)" | chart count BY host,user
0 Karma

sundareshr
Legend

What does the log entry look like? Can you share one event with successful logon and one with failed logon?

0 Karma
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