You're new windows decoder rules work great!  I'm going to throw them at my 
hosts right now (better than what I've got at the moment!).

However, I'm thinking there's a bug somewhere in some pattern matching code 
somewhere. However, I don't know yet if it's a bug in the current atomic 
RPMs or the ossec code.  But, I did some further testing and here's what I 
found.

Set up fresh install of ossec server 2.9.0, edited ossec.conf and removed 
all rules and then created an empty etc/decoder.xml with following:

<decoder name="windows">
  <type>windows</type>
  <prematch>^\d\d\d\d \w\w\w \d\d \d\d:\d\d</prematch>
</decoder>

<!-- EOF -->
 

Then fired up 'ossec-logtest -vd' and executed the following test entries 
against it:


full test with a string that should work - complete fail

2017 Feb 08 19:00:00 WinEvtLog

**Phase 1: Completed pre-decoding.
       full event: '2017 Feb 08 19:00:00 WinEvtLog'
       hostname: 'gopher-test'
       program_name: '(null)'
       log: 'WinEvtLog'

**Phase 2: Completed decoding.
       No decoder matched.

 

short string - remove everything except the date stamp, no whitespace at 
end – everything works

2017 Feb 08 19:00:00  

**Phase 1: Completed pre-decoding.
       full event: '2017 Feb 08 19:00:00'
       hostname: 'gopher-test'
       program_name: '(null)'
       log: '2017 Feb 08 19:00:00'

**Phase 2: Completed decoding.
       decoder: 'windows'
 

same short string - ADD ONE SPACE AT END - EVERYTHING FAILS. That pattern 
match should NOT be puking because of an extra space at the end as far as I 
can tell.


2017 Feb 08 19:00:00           

**Phase 1: Completed pre-decoding.
       full event: '2017 Feb 08 19:00:00 '
       hostname: 'gopher-test'
       program_name: '(null)'
       log: ''

**Phase 2: Completed decoding.
       No decoder matched.


Anyway, thanks for the help!  I'll keep you posted if there's any more 
headaches with my windows logs.

 


On Thursday, February 9, 2017 at 2:57:57 PM UTC-5, dan (ddpbsd) wrote:
>
> Thanks for pointing this out. It's definitely shown me a(nother) gap 
> in our rules testing setup. 
> I'm guessing a 2.9.1 will be coming in shortly with the changes we 
> made to the windows decoders backported from master. 
> Here are the new decoders if you want to give them a spin: 
> <decoder name="windows"> 
>   <type>windows</type> 
>   <program_name>^WinEvtLog</program_name> 
> </decoder> 
>
> <decoder name="windows1"> 
>   <type>windows</type> 
>   <parent>windows</parent> 
>   <regex offset="after_parent">^\.+: (\w+)\((\d+)\): (\.+): </regex> 
>   <regex>(\.+): \.+: (\S+): </regex> 
>   <order>status, id, extra_data, user, system_name</order> 
>   <fts>name, location, system_name</fts> 
> </decoder> 
>
> <decoder name="windows1"> 
>   <type>windows</type> 
>   <parent>windows</parent> 
>   <regex> Source Network Address: (\S+)</regex> 
>   <order>srcip</order> 
> </decoder> 
>
> <decoder name="windows1"> 
>   <type>windows</type> 
>   <parent>windows</parent> 
>   <regex> Account Name: (\S+) Account</regex> 
>   <order>user</order> 
> </decoder> 
>
>
> On Thu, Feb 9, 2017 at 10:50 AM, Chris Snyder <dago...@gmail.com 
> <javascript:>> wrote: 
> > I just updated my CentOS 6 OSSEC server using the Atomic RPMs from 
> 2.8.3-53 
> > to 2.9.0-48. 
> > 
> > Before the updates, my Windows server logs were process fine. After the 
> > updates, ALL my windows logs are no longer being decoded correctly. 
> > 
> > Using ossec-logtest, and a test log entry of 
> > 
> > 2017 Feb 08 19:00:00 WinEvtLog: Security: AUDIT_SUCCESS(4738): 
> > Microsoft-Windows-Security-Auditing: (no user): 
> > 
> > With 2.8.3-53, logtest reports: 
> > 
> > **Phase 1: Completed pre-decoding. 
> >        full event: '2017 Feb 08 19:00:00 WinEvtLog: Security: 
> > AUDIT_SUCCESS(4738): Microsoft-Windows-Security-Auditing: (no user):' 
> >        hostname: 'mybox' 
> >        program_name: '(null)' 
> >        log: '2017 Feb 08 19:00:00 WinEvtLog: Security: 
> AUDIT_SUCCESS(4738): 
> > Microsoft-Windows-Security-Auditing: (no user):' 
> > 
> > **Phase 2: Completed decoding. 
> >        decoder: 'windows' 
> > 
> > With 2.9.0, logtest reports: 
> > 
> > **Phase 1: Completed pre-decoding. 
> >        full event: '2017 Feb 08 19:00:00 WinEvtLog: Security: 
> > AUDIT_SUCCESS(4738): Microsoft-Windows-Security-Auditing: (no user):' 
> >        hostname: 'mybox' 
> >        program_name: 'WinEvtLog' 
> >        log: 'Security: AUDIT_SUCCESS(4738): 
> > Microsoft-Windows-Security-Auditing: (no user):' 
> > 
> > **Phase 2: Completed decoding. 
> >        No decoder matched. 
> > 
> > BUT! If I drop off the date stamp prefix and just use the rest of the 
> line, 
> > IT WORKS! 
> > 
> > WinEvtLog: Security: AUDIT_SUCCESS(4738): 
> > Microsoft-Windows-Security-Auditing: (no user): 
> > 
> > **Phase 1: Completed pre-decoding. 
> >        full event: 'WinEvtLog: Security: AUDIT_SUCCESS(4738): 
> > Microsoft-Windows-Security-Auditing: (no user):' 
> >        hostname: 'tmgweb01' 
> >        program_name: '(null)' 
> >        log: 'WinEvtLog: Security: AUDIT_SUCCESS(4738): 
> > Microsoft-Windows-Security-Auditing: (no user):' 
> > 
> > **Phase 2: Completed decoding. 
> >        decoder: 'windows' 
> > 
> > I've tried to play with the windows WinEvt decoder definition but I 
> haven't 
> > had any luck getting it to match with the date stamp. 
> > 
> > I will say that my Windows servers are still running the 2.8.3 clients 
> > because I can't find an install package for 2.9.0 yet. 
> > 
> > Any ideas what's going on here? Help! 
> > 
> > -- 
> > 
> > --- 
> > You received this message because you are subscribed to the Google 
> Groups 
> > "ossec-list" group. 
> > To unsubscribe from this group and stop receiving emails from it, send 
> an 
> > email to ossec-list+...@googlegroups.com <javascript:>. 
> > For more options, visit https://groups.google.com/d/optout. 
>

-- 

--- 
You received this message because you are subscribed to the Google Groups 
"ossec-list" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to ossec-list+unsubscr...@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

Reply via email to