Logstash Regex Unrecognized character escape

[james.garside]

Hello all,

I have this regex which is working for most names but throws an error for some.

It seems my use of escape charaters is wrong.

[client][user][name] =~ /staff\\.*/  or [client][user][name] =~ /students\\.*/  

The error is below. (I've changed the surname)

[2020-03-19T17:49:54,758][WARN ][logstash.filters.elasticsearch][filebeat-firewall] Failed to query elasticsearch for previous event {:index=>"winlogbeat-*", :error=>"Unrecognized character escape 's' (code 115)\n at [Source: (byte[])\"{\n    \"size\": 1,\n    \"query\" : {\n      \"bool\":{\n\"must\" : [\n{\n\"range\": {\n\"@timestamp\": {\n\"gte\": \"now-2h\",\n \"lte\": \"now/d\"\n}\n}\n},\n{\n \"term\" : {\n\"winlog.event_data.FullyQualifiedSubjectUserName\": \"staff\\shaneed.smith\"\n }\n }\n]\n}\n},\n\"[truncated 53 bytes]; line: 16, column: 83]"}

Here is the query used by logstash.

{
    "size": 1,
    "query" : {
      "bool":{
          "must" : [
              {
                  "range": {
                      "@timestamp": {
                          "gte": "now-2h",
                          "lte": "now/d"
                      }
                  }
              },
              {
                  "term" : {
                       "winlog.event_data.ClientIPAddress": "%{[client][ip]}"
                  }
              }
          ]
      }
  },
  "_source": ["winlog.event_data.SubjectUserName"]
}

Any help would be greatly appreciated.

James