topic Re: Help building regex for searches based on cs_username field. in Splunk Search

Help building regex for searches based on cs_username field.

Vfinney — Wed, 20 May 2020 18:48:41 GMT

I'm having no luck building a regex to match cs_usernames. What I'm looking for are two separate searches both based on the
cs_username field. The first search is to find all instances where the usernames are in all CAPS. The second search is to find usernames that end in at least two digits. Example of logs are below:

2020-05-15 04:58:34 10.140.14.228 POST /NotAvailable.aspx - 80 Gerardot 10.140.15.235 Mozilla/5.0+(Linux;+Android+9;+SM-G960U)+AppleWebKit/537.36+(KHTML,+like+Gecko)+Chrome/74.0.3729.136+Mobile+Safari/537.36  302 0 0 15 172.69.69.111

2020-05-15 04:57:19 10.140.14.228 POST /Account/Login.aspx - 80 Kaitlyn1230 10.140.15.235 Mozilla/5.0+(iPhone;+CPU+iPhone+OS+13_4+like+Mac+OS+X)+AppleWebKit/605.1.15+(KHTML,+like+Gecko)+GSA/107.0.310639584+Mobile/15E148+Safari/604.1 200 0 0 46 162.158.75.109

2020-05-15 04:54:24 10.140.14.228 POST /PaymentInfo.aspx - 80 Emulbah 10.140.15.235 Mozilla/5.0+(Windows+NT+6.1;+Win64;+x64)+AppleWebKit/537.36+(KHTML,+like+Gecko)+Chrome/81.0.4044.138+Safari/537.36  302 0 0 46 172.68.150.39

Re: Help building regex for searches based on cs_username field.

to4kawa — Wed, 20 May 2020 21:11:20 GMT

your log is space delimited.

why do not you use \s and \S?

or try Field Extracter

Re: Help building regex for searches based on cs_username field.

gcusello — Wed, 20 May 2020 21:53:42 GMT

Hi @Vfinney,
try the following regex

^\d+-\d+-\d+\s+\d+:\d+:\d+\s+\d+\.\d+\.\d+\.\d+\s+\w+\s\/[^ ]+\s+[^ ]+\s+\d+\s+(?<cs_username>[^ ]+)\s+

or using the rex command

your_search
| rex "^\d+-\d+-\d+\s+\d+:\d+:\d+\s+\d+\.\d+\.\d+\.\d+\s+\w+\s\/[^ ]+\s+[^ ]+\s+\d+\s+(?<cs_username>[^ ]+)\s+"
| ...

that you can test at https://regex101.com/r/xyPcQj/1

Ciao.
Giuseppe