Splunk Search

Using blacklist on Windows TA and XML events

dieguiariel
Path Finder

Hi, ive successfully blacklisted the windows event 4658 with this line_

blacklist2 = $XmlRegex="<EventID>4658<\/EventID>.*<Data Name='ProcessName'>[C-F]:\\Windows\\System32\\CpqMgmt\\cqmghost\\cqmghost.exe"

ive tried to do the same for event 4656

blacklist1 = $XmlRegex="<EventID>4656<\/EventID>.*<Data Name='ProcessName'>[C-F]:\\Windows\\System32\\CpqMgmt\\cqmghost\\cqmghost.exe"

 

but isn't working. Any ideas?

 

inputs.conf:

 

[WinEventLog://Security]
disabled = 0
index = winevents

whitelist1 = 1102,4616,4647,4656-4658,4660,4663,4670,4672
whitelist2 = 4673,4674,4698-4702,4704,4705,4715,4719,4720
whitelist3 = 4722,4725,4726,4732,4733,4735,4738-4740,4767
whitelist3 = 4779,5140,5145

blacklist1 = $XmlRegex="<EventID>4656<\/EventID>.*<Data Name='ProcessName'>[C]:\\Windows\\System32\\CpqMgmt\\cqmghost\\cqmghost.exe"
blacklist2 = $XmlRegex="<EventID>4658<\/EventID>.*<Data Name='ProcessName'>[C-F]:\\Windows\\System32\\CpqMgmt\\cqmghost\\cqmghost.exe"

 

Raw event example

<Event xmlns='http://schemas.microsoft.com/win/2004/08/events/event'><System><Provider Name='Microsoft-Windows-Security-Auditing' Guid='{54849625-5478-4994-A5BA-3E3B0328C30D}'/><EventID>4656</EventID><Version>1</Version><Level>0</Level><Task>12801</Task><Opcode>0</Opcode><Keywords>0x8020000000000000</Keywords><TimeCreated SystemTime='2020-08-12T19:47:25.544399300Z'/><EventRecordID>1397935969</EventRecordID><Correlation/><Execution ProcessID='716' ThreadID='728'/><Channel>Security</Channel><Computer>svr-apl-cit-01.BANCOREGIONAL.LOCAL</Computer><Security/></System><EventData><Data Name='SubjectUserSid'>NT AUTHORITY\SYSTEM</Data><Data Name='SubjectUserName'>SVR-APL-CIT-01$</Data><Data Name='SubjectDomainName'>BANCOREGIONAL</Data><Data Name='SubjectLogonId'>0x3e7</Data><Data Name='ObjectServer'>Security</Data><Data Name='ObjectType'>Key</Data><Data Name='ObjectName'>\REGISTRY\MACHINE\SYSTEM\ControlSet001\Services\SamSs</Data><Data Name='HandleId'>0x584</Data><Data Name='TransactionId'>{00000000-0000-0000-0000-000000000000}</Data><Data Name='AccessList'>%%1537 %%1538 %%1539 %%1540 %%4432 %%4433 %%4434 %%4435 %%4436 %%4437 </Data><Data Name='AccessReason'>-</Data><Data Name='AccessMask'>0xf003f</Data><Data Name='PrivilegeList'>-</Data><Data Name='RestrictedSidCount'>0</Data><Data Name='ProcessId'>0x1ec0</Data><Data Name='ProcessName'>C:\Windows\System32\CpqMgmt\cqmghost\cqmghost.exe</Data><Data Name='ResourceAttributes'>-</Data></EventData></Event>

Thanks in advance.

Labels (1)
0 Karma

gcusello
SplunkTrust
SplunkTrust

Hi @dieguiariel,

you have to escape all the special chars in your regex (also <, \, =,  ', etc...).

So your regex should be something like these:

\<EventID\>4656\<\/EventID\>.*\<Data Name\=\'ProcessName\'\>(C|D|E|F):\\\\Windows\\\\System32\\\\CpqMgmt\\\\cqmghost\\\\cqmghost\.exe

 Ciao.

Giuseppe

0 Karma

dieguiariel
Path Finder

Hi!, it didn't work.

 

Finally i fixed like this:

blacklist1 = $XmlRegex="<Data Name='ProcessName'>[C]:\\Windows\\System32\\CpqMgmt\\cqmghost\\cqmghost.exe"

because i've needed filter this process from both event codes.

Don't know why didn't work the first way.

Thanks anyway.

0 Karma

gcusello
SplunkTrust
SplunkTrust

Hi @dieguiariel,

the regex to filter the events is:

\<EventID\>4656\<\/EventID\>.*\<Data Name\=\'ProcessName\'\>(C|D|E|F):\\Windows\\System32\\CpqMgmt\\cqmghost\\cqmghost\.exe

that you can check at https://regex101.com/r/a3QYcF/1

As I said, you have to escape all the special chars in your regex (also <, \, =,  ', etc...).

Ciao.

Giuseppe

0 Karma
Get Updates on the Splunk Community!

Splunk Observability for AI

Don’t miss out on an exciting Tech Talk on Splunk Observability for AI!Discover how Splunk’s agentic AI ...

Splunk Enterprise Security 8.x: The Essential Upgrade for Threat Detection, ...

Watch On Demand the Tech Talk, and empower your SOC to reach new heights! Duration: 1 hour  Prepare to ...

Splunk Observability as Code: From Zero to Dashboard

For the details on what Self-Service Observability and Observability as Code is, we have some awesome content ...