Issue in retrieving value of a key from JSON format windows nxlog


#1 anilbqkumar

Hi Folks,

We are testing nxlog for syslog forwarder as replacment for EvtSys. We are facing issue in retriving keys from JSON format message. Suppose in this case we want to get value for a key "Account Name". Can you please help us how can we get value for this key.

Below is the code and nxlog generated windows log sample (collected from syslog server). Can you please let us know what went wrong here. how can achieve any key from the JSON.

Below is Sample code snippet----------------------------- filter { grok { match => {"message" => "%{MONTH:month}(?:\s|\s\s)%{MONTHDAY:day}\s(?<time> [0-9][:][0-9]*[:][0-9][0-9])\s%{IPV4:src_ip}\s%{GREEDYDATA:json_msg}"} add_field => [ "received_at", "%{@timestamp}" ] add_field => [ "received_from", "%{host}" ] } json{ source => "json_msg" target => "\r\n\tAccount Name:\t\t" } }

Below is Sample Log snippet generated by nxlog----------------------------- May 4 10:31:06 10.248.15.57 {"EventTime": "2021-05-04 10:30:16","Hostname":"WindowsHostMachine","Keywords":-9214364837600034816,"EventType":"AUDIT_SUCCESS","SeverityValue":2,"Severity":"INFO","EventID":4624,"SourceName":"Microsoft-Windows-Security-Auditing","ProviderGuid":"{54849625-5478-4994-A5BA-3E3B0328C30D}","Version":1,"Task":12544,"OpcodeValue":0,"RecordNumber":2002203,"ProcessID":668,"ThreadID":8076,"Channel":"Security","Message":"An account was successfully logged on.\r\n\r\nSubject:\r\n\tSecurity ID:\t\tS-1-0-0\r\n\tAccount Name:\t\t-\r\n\tAccount Domain:\t\t-\r\n\tLogon ID:\t\t0x0\r\n\r\nLogon Type:\t\t\t3\r\n\r\nImpersonation Level:\t\tImpersonation\r\n\r\nNew Logon:\r\n\tSecurity ID:\t\tS-1-5-21-3128912327-2939948577-25280133-30353\r\n\tAccount Name:\t\tanil.jr.kumar\r\n\tAccount Domain:\t\tNEXTGENTest\r\n\tLogon ID:\t\t0x3B3055EE\r\n\tLogon GUID:\t\t{00000000-0000-0000-0000-000000000000}\r\n\r\nProcess Information:\r\n\tProcess ID:\t\t0x0\r\n\tProcess Name:\t\t-\r\n\r\nNetwork Information:\r\n\tWorkstation Name:\tHDC3-L-F25D2EZ\r\n\tSource Network Address:\t-\r\n\tSource Port:\t\t-\r\n\r\nDetailed Authentication Information:\r\n\tLogon Process:\t\tNtLmSsp \r\n\tAuthentication Package:\tNTLM\r\n\tTransited Services:\t-\r\n\tPackage Name (NTLM only):\tNTLM V2\r\n\tKey Length:\t\t128\r\n\r\nThis event is generated when a logon session is created. It is generated on the computer that was accessed.\r\n\r\nThe subject fields indicate the account on the local system which requested the logon. This is most commonly a service such as the Server service, or a local process such as Winlogon.exe or Services.exe.\r\n\r\nThe logon type field indicates the kind of logon that occurred. The most common types are 2 (interactive) and 3 (network).\r\n\r\nThe New Logon fields indicate the account for whom the new logon was created, i.e. the account that was logged on.\r\n\r\nThe network fields indicate where a remote logon request originated. Workstation name is not always available and may be left blank in some cases.\r\n\r\nThe impersonation level field indicates the extent to which a process in the logon session can impersonate.\r\n\r\nThe authentication information fields provide detailed information about this specific logon request.\r\n\t- Logon GUID is a unique identifier that can be used to correlate this event with a KDC event.\r\n\t- Transited services indicate which intermediate services have participated in this logon request.\r\n\t- Package name indicates which sub-protocol was used among the NTLM protocols.\r\n\t- Key length indicates the length of the generated session key. This will be 0 if no session key was requested.","Category":"Logon","Opcode":"Info","SubjectUserSid":"S-1-0-0","SubjectUserName":"-","SubjectDomainName":"-","SubjectLogonId":"0x0","TargetUserSid":"S-1-5-21-3128912327-2939948577-25280133-30353","TargetUserName":"anil.jr.kumar","TargetDomainName":"tNEXTGENTest","TargetLogonId":"0x3b3055ee","LogonType":"3","LogonProcessName":"NtLmSsp ","AuthenticationPackageName":"NTLM","WorkstationName":"HDC3-L-F25D2EZ","LogonGuid":"{00000000-0000-0000-0000-000000000000}","TransmittedServices":"-","LmPackageName":"NTLM V2","KeyLength":"128","ProcessName":"-","IpAddress":"-","IpPort":"-","ImpersonationLevel":"%%1833","EventReceivedTime":"2021-05-04 10:30:17","SourceModuleName":"eventlog","SourceModuleType":"im_msvistalog"}