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ChristopherKerry's avatar
ChristopherKerry
Copper Contributor
Mar 16, 2021

Searching by more than one field when using a watch list

Hi there,   I'm trying to filter by multiple fields in a watchlist. Something similar to the below, but with the fields user, src and dest.   | where SrcIP !in ((_GetWatchlist('WL_Global') | proj...
Ofer_Shezaf's avatar
Ofer_Shezaf
Icon for Microsoft rankMicrosoft
Mar 17, 2021

ChristopherKerry 

 

This is what I really find challenging with Splunk. Queries are absolutely unreadable. The SPL example you brought is fast to write to the initiated but does make any sense logically, making it impossible to understand if you are not a Splunk Guru.

 

In KQL you have to be explicit, and readable, but I don't think makes the optimization different.

  • ChristopherKerry's avatar
    ChristopherKerry
    Copper Contributor
    Mar 18, 2021

    Ofer_Shezaf I would definitely say this is easier to read and quicker to write (especially when you have a lot of query to go through):

    | search NOT [| inputlookup LOOKUP | fields src dest dest_port app protocol url]

     

    than this:

    | where SrcIP !in ((_GetWatchlist('LOOKUP') | project SrcIP))
| where Dest !in ((_GetWatchlist('LOOKUP') | project Dest))
| where DestPort !in ((_GetWatchlist('LOOKUP') | project DestPort))
| where App !in ((_GetWatchlist('LOOKUP') | project App))
| where Protocol !in ((_GetWatchlist('LOOKUP') | project Protocol))
| where Url !in ((_GetWatchlist('LOOKUP') | project Url))

     

    Even more so when you have 3 or 4 lookups to correlate and you can end up with 10+ lines of KQL just for a few lookups.

     

    Is there a better way to store this information and correlate it in Sentinel?

    • BOTCCoop's avatar
      BOTCCoop
      Copper Contributor
      Mar 18, 2021

      ChristopherKerry Ofer_Shezaf 
      To expand on this:

       

      | search NOT [| inputlookup LOOKUP | fields src dest dest_port app

       

      Splunk is parsing all the fields or columns you currently have available and matching them to the lookup, it then compares the value of that field and when it finds a match removes the result from our search.

       

      I suppose a less verbose but similar approach in KQL land would be:

       

      | where (SrcIP or User or Dest) !in ((_GetWatchlist('WL_Global') | project user, src, dest

       

      Currently, the above doesn't work and you do have to individually split out your where filtering:

      I can see both sides, but it's far more verbose in KQL making readability more of a struggle.

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