Thanks for the input! I'll take a closer look at 2.8.3 but the whole reason I was looking at 2.9RC2 was because it supported the eventchannel log type. >From what I understand, 2.8.x had trouble with this and therefore had trouble with sysmon. Has that been your experience with 2.8.3? Thanks again everyone for the help.
On Tue, Aug 2, 2016 at 8:49 PM, lostinthetubez <[email protected]> wrote: > Craig, > > > > Hm... I just now noticed your exact symptoms while playing with a test > OSSEC server that was created from a relatively recent git clone of the > repository (cloned within the last month or two?). Take a look at your > original output of ossec-logtest, under “Prepended Data Removed”. Look at > the parsed “log:” field. Ossec-logtest is stripping “2016 Jul 29 22:32:24 > WinEvtLog:” before processing it against the decoders. It isn’t supposed to > be doing this. At least, this was not the behavior under 2.8.3. I do not > have time to test the latest build from the repo to see if this problem has > been fixed, though you might give that a whirl if you have the luxury of > time. If you just want to make things work correctly, build your OSSEC > server from the last known-good release, which is 2.8.3, or just follow > Jesus’ suggestion and try out the Wazuh build. > > > > > > *From:* [email protected] [mailto:[email protected]] *On > Behalf Of *Craig > *Sent:* Sunday, July 31, 2016 3:14 PM > *To:* ossec-list <[email protected]> > *Subject:* Re: [ossec-list] eventchannel decoder testing > > > > Great, thank you. That does help troubleshoot. So, I do have a follow up > question. Here is the default decoder: > > > > <decoder name="Sysmon-EventID#1"> > > <type>windows</type> > > <prematch>INFORMATION\(1\)</prematch> > > <regex offset="after_prematch">Image: (\.*) \s*CommandLine: \.* \s*User: > (\.*) \s*LogonGuid: \S* \s*LogonId: \S* \s*TerminalSessionId: \S* > \s*IntegrityLevel: \.*HashType: \S* \s*Hash: (\S*) \s*ParentProcessGuid: > \S* \s*ParentProcessID: \S* \s*ParentImage: (\.*) > \s*ParentCommandLine:</regex> > > <order>status,user,url,data</order> > > </decoder> > > > > However, when I remove the prepended data from my archives.log file and > send it through logtest, the decoder doesn't work (if I leave the prepended > data there, the decoder works). Any ideas why this might be happening? See > below for my logtest: > > > > *Prepended Data Removed:* > > > > **Phase 1: Completed pre-decoding. > > full event: '2016 Jul 29 22:32:24 WinEvtLog: > Microsoft-Windows-Sysmon/Operational: INFORMATION(1): > Microsoft-Windows-Sysmon: SYSTEM: NT AUTHORITY: Win7-x64-PC1.hackme.local: > Process Create: UtcTime: 2016-07-30 03:32:24.846 ProcessGuid: > {67C360F4-1FC8-579C-0000-001017F41E00} ProcessId: 3988 Image: > C:\Users\administrator\Desktop\svchost.exe CommandLine: > "C:\Users\administrator\Desktop\svchost.exe" CurrentDirectory: > C:\Users\administrator\Desktop\ User: HACKME\Administrator LogonGuid: > {67C360F4-1C55-579C-0000-00206BBC0600} LogonId: 0x6bc6b > TerminalSessionId: 1 IntegrityLevel: High Hashes: > MD5=C019D10F80409FC4C7D45EBFA48B0076 ParentProcessGuid: > {67C360F4-1C57-579C-0000-001092EC0600} ParentProcessId: 3056 ParentImage: > C:\Windows\explorer.exe ParentCommandLine: C:\Windows\Explorer.EXE' > > hostname: 'ubuntu-srv1' > > program_name: 'WinEvtLog' > > log: 'Microsoft-Windows-Sysmon/Operational: INFORMATION(1): > Microsoft-Windows-Sysmon: SYSTEM: NT AUTHORITY: Win7-x64-PC1.hackme.local: > Process Create: UtcTime: 2016-07-30 03:32:24.846 ProcessGuid: > {67C360F4-1FC8-579C-0000-001017F41E00} ProcessId: 3988 Image: > C:\Users\administrator\Desktop\svchost.exe CommandLine: > "C:\Users\administrator\Desktop\svchost.exe" CurrentDirectory: > C:\Users\administrator\Desktop\ User: HACKME\Administrator LogonGuid: > {67C360F4-1C55-579C-0000-00206BBC0600} LogonId: 0x6bc6b > TerminalSessionId: 1 IntegrityLevel: High Hashes: > MD5=C019D10F80409FC4C7D45EBFA48B0076 ParentProcessGuid: > {67C360F4-1C57-579C-0000-001092EC0600} ParentProcessId: 3056 ParentImage: > C:\Windows\explorer.exe ParentCommandLine: C:\Windows\Explorer.EXE' > > > > ***Phase 2: Completed decoding.* > > * No decoder matched.* > > > > *Prepended Data Intact:* > > > > **Phase 1: Completed pre-decoding. > > full event: '*2016 Jul 29 22:32:25 (WIN7-X64-PC1) > 172.16.213.5->WinEvtLog* 2016 Jul 29 22:32:24 WinEvtLog: > Microsoft-Windows-Sysmon/Operational: INFORMATION(1): > Microsoft-Windows-Sysmon: SYSTEM: NT AUTHORITY: Win7-x64-PC1.hackme.local: > Process Create: UtcTime: 2016-07-30 03:32:24.846 ProcessGuid: > {67C360F4-1FC8-579C-0000-001017F41E00} ProcessId: 3988 Image: > C:\Users\administrator\Desktop\svchost.exe CommandLine: > "C:\Users\administrator\Desktop\svchost.exe" CurrentDirectory: > C:\Users\administrator\Desktop\ User: HACKME\Administrator LogonGuid: > {67C360F4-1C55-579C-0000-00206BBC0600} LogonId: 0x6bc6b > TerminalSessionId: 1 IntegrityLevel: High Hashes: > MD5=C019D10F80409FC4C7D45EBFA48B0076 ParentProcessGuid: > {67C360F4-1C57-579C-0000-001092EC0600} ParentProcessId: 3056 ParentImage: > C:\Windows\explorer.exe ParentCommandLine: C:\Windows\Explorer.EXE' > > hostname: '(WIN7-X64-PC1)' > > program_name: '(null)' > > log: '172.16.213.5->WinEvtLog 2016 Jul 29 22:32:24 WinEvtLog: > Microsoft-Windows-Sysmon/Operational: INFORMATION(1): > Microsoft-Windows-Sysmon: SYSTEM: NT AUTHORITY: Win7-x64-PC1.hackme.local: > Process Create: UtcTime: 2016-07-30 03:32:24.846 ProcessGuid: > {67C360F4-1FC8-579C-0000-001017F41E00} ProcessId: 3988 Image: > C:\Users\administrator\Desktop\svchost.exe CommandLine: > "C:\Users\administrator\Desktop\svchost.exe" CurrentDirectory: > C:\Users\administrator\Desktop\ User: HACKME\Administrator LogonGuid: > {67C360F4-1C55-579C-0000-00206BBC0600} LogonId: 0x6bc6b > TerminalSessionId: 1 IntegrityLevel: High Hashes: > MD5=C019D10F80409FC4C7D45EBFA48B0076 ParentProcessGuid: > {67C360F4-1C57-579C-0000-001092EC0600} ParentProcessId: 3056 ParentImage: > C:\Windows\explorer.exe ParentCommandLine: C:\Windows\Explorer.EXE' > > > > ***Phase 2: Completed decoding.* > > * decoder: 'Sysmon-EventID#1'* > > > > > > > > > > > On Friday, July 29, 2016 at 11:22:46 AM UTC-5, LostInThe Tubez wrote: > > Delving into Sysmon event log parsing reveals just how monumental a task > it is to parse out useful information from Windows event logs. The > challenge is that nearly each and every Event ID has a different log > format, which essentially means that almost every Event ID needs its own > decoder... I may be waxing a little dramatic here, but the point is that to > properly parse Windows logs, the original decoder needs to be made more > generic and LOTS more child decoders need to be developed. At least, that > is the approach I took, personally. Maybe I’m totally off base. Been > testing it for a few months and it seems to work OK, but I haven’t done any > auditing to see if I’ve broken anything. Anyway, here’s what I did and what > works for me at the moment. If you go this route, you’ll need to comment > out the original windows decoder in /var/ossec/etc/decoder.xml (and > whatever else sysmon-related might have made it in there since last I > looked; I’m not running the latest beta). I put these in local_decoder.xml: > > > > <decoder name="windows"> > > <type>windows</type> > > <prematch>^\d\d\d\d \w\w\w \d\d \d\d:\d\d:\d\d WinEvtLog: > |^WinEvtLog: </prematch> > > </decoder> > > > > <decoder name="windows-defaultlogs"> > > <parent>windows</parent> > > <type>windows</type> > > <use_own_name>true</use_own_name> > > <prematch offset="after_parent">^Application: |^Security: > |^System: </prematch> > > <regex offset="after_parent">^\.+: (\w+)\((\d+)\): (\.+): </regex> > > <regex>(\.+): \.+: (\S+): </regex> > > <order>status, id, extra_data, user, system_name</order> > > <fts>name, location, user, system_name</fts> > > </decoder> > > > > <decoder name="windows-sysmon-eventID1"> > > <parent>windows</parent> > > <type>windows</type> > > <prematch > offset="after_parent">^Microsoft-Windows-Sysmon/Operational: > INFORMATION\(1\)</prematch> > > <regex > offset="after_parent">^Microsoft-Windows-Sysmon/Operational: (\w+)\((\d)\): > Microsoft-Windows-Sysmon: SYSTEM: NT AUTHORITY: (\S+): Process Create: \.+ > ProcessId: \d+ Image: (\.*) CommandLine: \.*</regex> > > <regex> User: (\.*) LogonGuid: \S* LogonId: \S* > TerminalSessionId: \d* IntegrityLevel: \w* Hashes: \w+=(\w*) > ParentProcessGuid: \S* ParentProcessID: \S* ParentImage: (\.+)</regex> > > <order>status, id, system_name, dstuser, srcuser, url, extra_data, > extra_data</order> > > </decoder> > > > > > > Put this in your local_rules.xml: > > <rule id="184600" level="1"> > > <if_sid>18101</if_sid> > > <id>^1$</id> > > <description>Sysmon Process Launch Event</description> > > </rule> > > > > If you haven’t done so already, it is always helpful to enable logall mode > when you’re working on new decoders. This will retain a copy of every > single log line sent to your OSSEC manager. In your ossec.conf on the > manager, put <logall>yes</logall> in a global tag somewhere and restart the > service. You will now have a record of all logs sent to the manager, not > just those that generate alerts. The current day’s archival logs are in > /var/ossec/logs/archives/archives.log. Note that in order to run these > particular logs through ossec-logtest, you’ll need to remove a prepended > bit of text. So, edit a log entry like this: > > > > 2016 Jul 29 08:33:17 (hostname) 100.200.123.123->WinEvtLog 2016 Jul 29 > 08:36:08 WinEvtLog: Microsoft-Windows-Sysmon/Operational: INFORMATION(1): > Microsoft-Windows-Sysmon: SYSTEM: NT AUTHORITY: > hostname.subdomain.domain.tld: Process Create: UtcTime: 2016-07-29 > 15:36:08.268 ProcessGuid: {A560AB96-77E8-579B-0000-0010B7B17E50} > ProcessId: 50292 Image: C:\Program Files (x86)\KeePass Password Safe > 2\KeePass.exe CommandLine: "C:\Program Files (x86)\KeePass Password Safe > 2\KeePass.exe" CurrentDirectory: C:\Program Files (x86)\KeePass Password > Safe 2\ User: domain\username LogonGuid: > {A560AB96-40DE-578E-0000-00209886AB02} LogonId: 0x2AB8698 > TerminalSessionId: 1 IntegrityLevel: Medium Hashes: > SHA1=5F5AC91EB83EFB6C4171AFF9EC1ED98EBA1C6A6C ParentProcessGuid: > {A560AB96-40E0-578E-0000-0010285AAC02} ParentProcessId: 7540 ParentImage: > C:\Windows\explorer.exe ParentCommandLine: C:\Windows\Explorer.EXE > > > > to become: > > 2016 Jul 29 08:36:08 WinEvtLog: Microsoft-Windows-Sysmon/Operational: > INFORMATION(1): Microsoft-Windows-Sysmon: SYSTEM: NT AUTHORITY: > hostname.subdomain.domain.tld: Process Create: UtcTime: 2016-07-29 > 15:36:08.268 ProcessGuid: {A560AB96-77E8-579B-0000-0010B7B17E50} > ProcessId: 50292 Image: C:\Program Files (x86)\KeePass Password Safe > 2\KeePass.exe CommandLine: "C:\Program Files (x86)\KeePass Password Safe > 2\KeePass.exe" CurrentDirectory: C:\Program Files (x86)\KeePass Password > Safe 2\ User: domain\username LogonGuid: > {A560AB96-40DE-578E-0000-00209886AB02} LogonId: 0x2AB8698 > TerminalSessionId: 1 IntegrityLevel: Medium Hashes: > SHA1=5F5AC91EB83EFB6C4171AFF9EC1ED98EBA1C6A6C ParentProcessGuid: > {A560AB96-40E0-578E-0000-0010285AAC02} ParentProcessId: 7540 ParentImage: > C:\Windows\explorer.exe ParentCommandLine: C:\Windows\Explorer.EXE > > > > before copy/pasting into ossec-logtest. This is the best way to go about > testing an eventchannel log. You get to see exactly what is decoded and > which rules are triggered. > > > > > > *From:* [email protected] [mailto:[email protected]] *On > Behalf Of *Craig > *Sent:* Thursday, July 28, 2016 8:24 PM > *To:* ossec-list <[email protected]> > *Subject:* [ossec-list] eventchannel decoder testing > > > > I am currently running 2.9RC2 on both client and server: > > > > What is the best way to go about testing an eventchannel log? I have the > following set in my local ossec.conf on my windows agent: > > > > <localfile> > > <location>Microsoft-Windows-Sysmon/Operational</location> > > <log_format>eventchannel</log_format> > > </localfile> > > > > I am using the default sysmon decoder included on my server: > > > > <decoder name="Sysmon-EventID#1"> > > <type>windows</type> > > <prematch>INFORMATION\(1\)</prematch> > > <regex offset="after_prematch">Image: (\.*) \s*CommandLine: \.* \s*User: > (\.*) \s*LogonGuid: \S* \s*LogonId: \S* \s*TerminalSessionId: \S* > \s*IntegrityLevel: \.*HashType: \S* \s*Hash: (\S*) \s*ParentProcessGuid: > \S* \s*ParentProcessID: \S* \s*ParentImage: (\.*) > \s*ParentCommandLine:</regex> > > <order>status,user,url,data</order> > > </decoder> > > > > I modified the default sysmon rule so that I would capture all process > creates by setting the level to 1: > > > > <rule id="184700" level="1"> > > <if_sid>18100</if_sid> > > <description>Sysmon - Process Create Event</description> > > </rule> > > > > > > I would think that i would now see all process creates in my alerts.log > but unfortunately I don't see any sysmon events at all. Any idea on the > best way to troubleshoot this? Thank you! > > > > > > -- > > --- > 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 [email protected]. > 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 [email protected]. > For more options, visit https://groups.google.com/d/optout. > > -- > > --- > You received this message because you are subscribed to a topic in the > Google Groups "ossec-list" group. > To unsubscribe from this topic, visit > https://groups.google.com/d/topic/ossec-list/X0uBpH1nEDE/unsubscribe. > To unsubscribe from this group and all its topics, send an email to > [email protected]. > 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 [email protected]. For more options, visit https://groups.google.com/d/optout.
