Getting Data In

Routing windows security logs to another index

lclayton95
Loves-to-Learn Everything

I am trying to route my windows security logs to another specified index but it has to meet certain criteria.

EventCode has to be 4688 and the Token Elevation Level equals either %%1936, %%1938, TokenElevationTypeDefault, TokenElevationTypeLimited.

So far i have written these regular expressions

1. REGEX = ((?s).*EventCode=4688*.)((?si).*(%%1936|TokenElevationTypeDefault|TokenElevationTypeLimited)*.)

2. REGEX = EventCode=4688.*TokenElevationType=(%%1936|%%1938|TokenElevationTypeDefault|TokenElevationTypeLimited)

When using 1, All eventcodes 4688 come to the specified index when i only wanted 1936 and 1938. I wanted to leave the %%1937 token in its original index.

When using 2, no data at all comes to the index even though its seems to be a much simpler regex. What am i missing to ensure 4688 is properly filter using transforms and props?

Labels (1)
0 Karma

lclayton95
Loves-to-Learn Everything

Yeah i been testing on regex 101 seem to be some delta in how splunk processes the regex however. For example this is what i have so far

https://regex101.com/r/95JbuG/1 

but when i add another event to this the regex stops working

0 Karma

marnall
Motivator

Could you try this regex:

(?s)EventCode=4688.*Token Elevation Type: (%%1936|%%1938|TokenElevationTypeDefault|TokenElevationTypeLimited)

And also post your (sanitized) props.conf and transforms.conf if it does not work?

0 Karma

marnall
Motivator

In Regex 1, you seem to have .* backwards (*.) in two instances, where the one near the end is particularly problematic, so if you have:

(%%1936|TokenElevationTypeDefault|TokenElevationTypeLimited)*.

Then it will match strings like %%1936, 0 or more times, so it will match events which don't include %%1936 or the other strings. 

Try removing the *. near the end. Also I recommend testing the regex on a site like regex101.com to make sure your regex is working before you put it in your splunk config.

Get Updates on the Splunk Community!

Developer Spotlight with Brett Adams

In our third Spotlight feature, we're excited to shine a light on Brett—a Splunk consultant, innovative ...

Index This | What can you do to make 55,555 equal 500?

April 2025 Edition Hayyy Splunk Education Enthusiasts and the Eternally Curious!  We’re back with this ...

Say goodbye to manually analyzing phishing and malware threats with Splunk Attack ...

In today’s evolving threat landscape, we understand you’re constantly bombarded with phishing and malware ...