Osquery

New in version 3.5.0.

It has been added a new Wazuh module which allows to manage the Osquery tool from Wazuh agents, being able to set the Osquery configuration and collect the generated information by Osquery to send it to the manager, generating the corresponding alerts if necessary.

How it works

Osquery can be used to expose an operating system as a high-performance relational database. This allows you to write SQL-based queries to explore operating system data.

Bellow you can see some examples of the queries we can make:

List all the local users of the machine.

SELECT * FROM users;

Get the process name, port, and PID, for processes listening on all interfaces.

SELECT DISTINCT processes.name, listening_ports.port, processes.pid
FROM listening_ports JOIN processes USING (pid)
WHERE listening_ports.address = '0.0.0.0';

Check the processes that have a deleted executable.

SELECT * FROM processes WHERE on_disk = 0;

A complete list of all the available tables can be found here.

Configuration

The first thing we need is to install Osquery in our system. To install Osquery we must go to the Osquery official page and download the compatible version.

Once we have it installed, we will need a configuration file for osquery. If you don’t have any, you can use the following one provided by Wazuh:

{
    "options": {
        "config_plugin": "filesystem",
        "logger_plugin": "filesystem",
        "utc": "true"
    },

    "schedule": {
        "system_info": {
        "query": "SELECT hostname, cpu_brand, physical_memory FROM system_info;",
        "interval": 3600
        },
        "high_load_average": {
        "query": "SELECT period, average, '70%' AS 'threshold' FROM load_average WHERE period = '15m' AND average > '0.7';",
        "interval": 900,
        "description": "Report if load charge is over 70 percent."
        },
        "low_free_memory": {
        "query": "SELECT memory_total, memory_free, CAST(memory_free AS real) / memory_total AS memory_free_perc, '10%' AS threshold FROM memory_info WHERE memory_free_perc < 0.1;",
        "interval": 1800,
        "description": "Free RAM is under 10%."
        }
    },

    "packs": {
        "osquery-monitoring": "/usr/share/osquery/packs/osquery-monitoring.conf",
        "incident-response": "/usr/share/osquery/packs/incident-response.conf",
        "it-compliance": "/usr/share/osquery/packs/it-compliance.conf",
        "vuln-management": "/usr/share/osquery/packs/vuln-management.conf",
        "hardware-monitoring": "/usr/share/osquery/packs/hardware-monitoring.conf",
        "ossec-rootkit": "/usr/share/osquery/packs/ossec-rootkit.conf"
    }
}

As you can see in this sample configuration, system_info, high_load_average and low_free_memory queries will be executed every hour.

Furthermore, this configuration uses some default packs such as osquery-monitoring, hardware-monitoring or ossec-rootkit among others. You can define you own packs and use it with this wodle.

Alert examples

Sample alert in log format:

** Alert 1532958886.437707: - osquery,
    2018 Jul 30 13:54:46 manager->osquery
    Rule: 24010 (level 3) -> 'osquery data grouped'
    {"name":"system_info","hostIdentifier":"manager","calendarTime":"Mon Jul 30 13:54:45 2018 UTC","unixTime":1532958885,"epoch":0,"counter":461,"columns":{"cgroup_namespace":"4026531835","cmdline":"","cwd":"/","disk_bytes_read":"0","disk_bytes_written":"0","egid":"0","euid":"0","gid":"0","ipc_namespace":"4026531839","mnt_namespace":"4026531840","name":"migration/0","net_namespace":"4026531957","nice":"0","on_disk":"-1","parent":"2","path":"","pgroup":"0","pid":"9","pid_namespace":"4026531836","resident_size":"","root":"/","sgid":"0","start_time":"0","state":"S","suid":"0","system_time":"2","threads":"1","total_size":"","uid":"0","user_namespace":"4026531837","user_time":"0","uts_namespace":"4026531838","wired_size":"0"},"action":"added"}
    name: system_info
    hostIdentifier: manager
    calendarTime: Mon Jul 30 13:54:45 2018 UTC
    unixTime: 1532958885
    epoch: 0
    counter: 461
    columns.cgroup_namespace: 4026531835
    columns.cmdline:
    columns.cwd: /
    columns.disk_bytes_read: 0
    columns.disk_bytes_written: 0
    columns.egid: 0
    columns.euid: 0
    columns.gid: 0
    columns.ipc_namespace: 4026531839
    columns.mnt_namespace: 4026531840
    columns.name: migration/0
    columns.net_namespace: 4026531957
    columns.nice: 0
    columns.on_disk: -1
    columns.parent: 2
    columns.path:
    columns.pgroup: 0
    columns.pid: 9
    columns.pid_namespace: 4026531836
    columns.resident_size:
    columns.root: /
    columns.sgid: 0
    columns.start_time: 0
    columns.state: S
    columns.suid: 0
    columns.system_time: 2
    columns.threads: 1
    columns.total_size:
    columns.uid: 0
    columns.user_namespace: 4026531837
    columns.user_time: 0
    columns.uts_namespace: 4026531838
    columns.wired_size: 0

And the same alert in JSON format:

{
"timestamp": "2018-07-30T13:54:46.476+0000",
"rule": {
    "level": 3,
    "description": "osquery data grouped",
    "id": "24010",
    "firedtimes": 207,
    "mail": false,
    "groups": [
    "osquery"
    ]
},
"agent": {
    "id": "000",
    "name": "manager"
},
"manager": {
    "name": "manager"
},
"id": "1532958886.437707",
"full_log": "{\"name\":\"system_info\",\"hostIdentifier\":\"manager\",\"calendarTime\":\"Mon Jul 30 13:54:45 2018 UTC\",\"unixTime\":1532958885,\"epoch\":0,\"counter\":461,\"columns\":{\"cgroup_namespace\":\"4026531835\",\"cmdline\":\"\",\"cwd\":\"/\",\"disk_bytes_read\":\"0\",\"disk_bytes_written\":\"0\",\"egid\":\"0\",\"euid\":\"0\",\"gid\":\"0\",\"ipc_namespace\":\"4026531839\",\"mnt_namespace\":\"4026531840\",\"name\":\"migration/0\",\"net_namespace\":\"4026531957\",\"nice\":\"0\",\"on_disk\":\"-1\",\"parent\":\"2\",\"path\":\"\",\"pgroup\":\"0\",\"pid\":\"9\",\"pid_namespace\":\"4026531836\",\"resident_size\":\"\",\"root\":\"/\",\"sgid\":\"0\",\"start_time\":\"0\",\"state\":\"S\",\"suid\":\"0\",\"system_time\":\"2\",\"threads\":\"1\",\"total_size\":\"\",\"uid\":\"0\",\"user_namespace\":\"4026531837\",\"user_time\":\"0\",\"uts_namespace\":\"4026531838\",\"wired_size\":\"0\"},\"action\":\"added\"}",
"decoder": {
    "name": "json"
},
"data": {
    "action": "added",
    "name": "system_info",
    "hostIdentifier": "manager",
    "calendarTime": "Mon Jul 30 13:54:45 2018 UTC",
    "unixTime": "1532958885",
    "epoch": "0",
    "counter": "461",
    "columns": {
        "cgroup_namespace": "4026531835",
        "cmdline": "",
        "cwd": "/",
        "disk_bytes_read": "0",
        "disk_bytes_written": "0",
        "egid": "0",
        "euid": "0",
        "gid": "0",
        "ipc_namespace": "4026531839",
        "mnt_namespace": "4026531840",
        "name": "migration/0",
        "net_namespace": "4026531957",
        "nice": "0",
        "on_disk": "-1",
        "parent": "2",
        "path": "",
        "pgroup": "0",
        "pid": "9",
        "pid_namespace": "4026531836",
        "resident_size": "",
        "root": "/",
        "sgid": "0",
        "start_time": "0",
        "state": "S",
        "suid": "0",
        "system_time": "2",
        "threads": "1",
        "total_size": "",
        "uid": "0",
        "user_namespace": "4026531837",
        "user_time": "0",
        "uts_namespace": "4026531838",
        "wired_size": "0"
    }
},
"predecoder": {
    "hostname": "manager"
},
"location": "osquery"
}

Note

If more than one report with the same content is received, only one alert will be generated the first time. The rest will be discarded.