Syslog Connector for Carbon Black Cloud


Keywords
carbonblack, carbon-black-cloud, cb-defense, cb-threathunter, endpoint-standard, enterprise-edr
License
MIT
Install
pip install cbc-syslog==2.0.3

Documentation

Carbon Black Cloud Syslog Connector 2.x

Introduction

The Carbon Black Cloud Syslog connector lets administrators forward alerts and audit logs from their Carbon Black Cloud instance to local, on-premise systems or other cloud applications.

Still need CBC Syslog 1.x? Checkout the legacy branch

If you are looking to migrate from CBC Syslog 1.x to 2.x take a look at the migration doc.

Features

  • Generates templated messages to support any desired syslog format or send the entire raw JSON message
  • Supports multi-tenancy of one or more Carbon Black Cloud organizations into a single syslog stream
  • Use local File, HTTP, TCP, encrypted (TCP over TLS), or UDP transport protocols to send data

Requirements

The following python packages are required to use CBC Syslog

  • carbon-black-cloud-sdk
  • Jinja2
  • psutil
  • tomli >= 1.1.0; python_version < '3.11'

Note: tomli is only required for python versions before 3.11 as tomlib has been included in the standard python library

Installation

You can install the Syslog Connector using either PyPI or GitHub.

PyPI Installation

pip install cbc-syslog

GitHub Installation

  1. Clone the repository using SSH or HTTPS

     SSH
     git clone git@github.com:carbonblack/cbc-syslog.git
    
     HTTPS
     git clone https://github.com/carbonblack/cbc-syslog.git
    
  2. Change to the CBC Syslog directory

     cd cbc-syslog
    
  3. Install python package

     pip install .
    

Running cbc_syslog_forwarder

The script cbc_syslog_forwarder is installed into the OS bin directory for easy access from any directory

>>> cbc_syslog_forwarder --help
usage: cbc_syslog_forwarder [-h] [--log-file LOG_FILE] [-d] [-v] {poll,history,convert,setup,check} ...

positional arguments:
  {poll,history,convert,setup,check}
                        The action to be taken
    poll                Fetches data from configured sources and forwards to configured output since last poll attempt
    history             Fetches data from specified source for specified time range and forwards to configured output
    convert             Convert CBC Syslog 1.0 conf to new 2.0 toml
    setup               Setup wizard to walkthrough configuration
    check               Check config for valid API keys with correct permissions

options:
  -h, --help            show this help message and exit
  --log-file LOG_FILE, -l LOG_FILE
                        Log file location
  -d, --debug           Set log level to debug
  -v, --verbose         Set log level to info

The cbc_syslog_forwarder poll command is designed to be executed in a cronjob or scheduled task for continual syslog forwarding

Mac/Linux:

Create a file to save the cronjob such as syslog-job.txt. Cronjobs use the UNIX cron format for specifying the schedule for the job to be executed

5  *  *  *  *  cbc_syslog_forwarder --log-file /some/path/cbc-syslog.log poll /some/path/my-config.toml

To start the job once the file is created run the following command

crontab syslog-job.txt

Windows:

Windows uses Task Scheduler for running scheduled applications.

  1. Search for Task Scheduler
  2. Click on Action then Create Task
  3. Name your Scheduled Task
  4. Click on the Actions Tab and Click New
  5. Under Program/script enter cbc_syslog_forwarder.
  6. Under Add arguments provide the arguments you use to run the poll command with absolute paths to any files
  7. Click OK
  8. Click on the Triggers tab and Click New
  9. Now is the time to schedule your Task. Fill out the information as needed and Click Ok

Your Task has been created! To test your Scheduled Task, follow these instructions below:

  1. Search for Task Scheduler
  2. Click on the folder Task Scheduler Library on the left hand column
  3. Select the Task you want to Test
  4. Select Run on the Actions column on the right hand column.

For more information on windows task scheduler checkout how-create-automated-task-using-task-scheduler

Create a Config file

If you are creating a CBC Syslog toml file for the first time checkout the setup wizard which walks you through the basic configuration steps.

cbc_syslog_forwarder setup my-config.toml

For more information on each section follow the guide below:

  1. Create a CUSTOM API key in at least one Carbon Black Cloud instance with the following permissions org.alerts READ and org.audits READ

    For more information on creating a CUSTOM API key see the Carbon Black Cloud User Guide

  2. Create a toml file - e.g. my-config.toml

    For a detailed breakdown of all the supported configurations see examples/cbc-syslog.toml.example

  3. Create the general section

     [general]
     backup_dir = "/some/dir"
     output_type = "file/http/tcp/tcp+tls/udp"
     output_format = "json/template"
    

    a. Specify an absolute path in backup_dir to a directory where unsent messages and previous state can be saved in the case of failure

    b. Decide how you would like to send the messages in output_type from file, http, tcp, tcp+tls or udp

    c. Decide your output_format from json or template

  4. Based on the output_type you have choosen you'll need to configure one of the following output destinations

    Examples outputs

     file_path = "/some/dir"
    
     http_out = "https://example.com"
     http_headers =  "{ \"content-type\": \"application/json\" }"
     https_ssl_verify = true
    
     tcp_out = "1.2.3.5:514"
    
     udp_out = "1.2.3.5:514"
    

    a. If you selected tcp+tls you'll need to configure the tls section based on your destination's expected certs

     [tls]
     ca_cert =
     cert =
     key =
     key_password =
     tls_verify =
    
  5. If you choose json for output_format skip to step 6 otherwise see 4a

    Example CEF template

     [alerts_template]
     template = "{{datetime_utc}} localhost CEF:1|{{vendor}}|{{product}}|{{product_version}}|{{reason_code}}|{{reason}}|{{severity}}|{{extension}}"
     type_field = "type"
     time_format = "%b %d %Y %H:%m:%S"
     time_fields = ["backend_timestamp"]
    
     [alerts_template.extension]
     default = "cat={{type}}\tact={{sensor_action}}\toutcome={{run_state}}"
     CB_ANALYTICS = "cat={{type}}\tact={{sensor_action}}\toutcome={{run_state}}\tframeworkName=MITRE_ATT&CK\tthreatAttackID={{attack_tactic}}:{{attack_technique}}"
    
     [audit_logs_template]
     template = "{{datetime_utc}} localhost CEF:1|{{vendor}}|{{product}}|{{product_version}}|Audit Logs|{{description}}|1|{{extension}}"
     time_format = "%b %d %Y %H:%m:%S"
     time_fields = ["eventTime"]
    
     [audit_logs_template.extension]
     default = "rt={{eventTime}}\tdvchost={{orgName}}\tduser={{loginName}}\tdvc={{clientIp}}\tcs4Label=Event_ID\tcs4={{eventId}}"
    

    a. You'll need to create a template for each data type you plan to enable

    b. Each data template supports a base template along with the option to specify an extension which can be used customize each message based on the values of the specified type_field

    In the example above the type_field for alerts is set to type which enables a different extension to be selected based on the alert field type

    Note: If a value is not specified in the extension then the default option will be used. The values are CASE_SENSITIVE

    c. If you need to modify the format of a timestamp then you can specify a python strftime format in time_format as well as the time_fields that need to be modified

    For more information on strftime formats see https://strftime.org/

    d. See Search Fields - Alert for the full list of Alert fields

  6. Configure one or more Carbon Black Cloud Organizations

    Example Organization

     [SourceName1]
     server_url = defense.conferdeploy.net
     org_key = ABCD1234
     custom_api_id = ABCDE12345
     custom_api_key = ABCDEFGHIKLMNO1234567890
     alerts_enabled = true
     audit_logs_enabled = true
    

    a. The server_url should match the hostname of your Carbon Black Cloud environment

    b. The org_key can be found on the API Access page in the Carbon Black Cloud console from step 1

    c. Use the CUSTOM API key from step 1

    d. Enable the desired data you would like to send for the organization

  7. If you set alerts_enabled to true then you will need to configure one or more alert_rules

    Each alert_rules is a separate request for alerts such that you can configure custom criteria for a desired usecase. See Search Fields - Alert for the fields marked Searchable.

    Example Alert Rules

     [[SourceName1.alert_rules]]
     type = [ "WATCHLIST", "DEVICE_CONTROL" ]
     minimum_severity = 7
    
     [[SourceName1.alert_rules]]
     type = [ "CB_ANALYTICS" ]
     minimum_severity = 3
    

    The key is the alert field you want to filter by and the value is a list of values you want to filter except minimum_severity which is a single integer. Each value is OR'd for a key and values are AND'd across keys e.g. type:( WATCHLIST OR DEVICE_CONTROL) AND minimum_severity: 7

    If you want to fetch ALL alerts then use the following alert_rules

     [[SourceName1.alert_rules]]
     minimum_severity = 1
    

Creating a custom message with templates

The configuration file provides the ability to define a template for each data type as well as the ability to create a custom extension which can be defined based on a configurable field to make a unique message for a data's sub type

The templates use jinja2 for rendering customizable messages. You can provide the text to be included as well as variable data by wrapping the field name in double curly braces e.g. {{field_name}}.

Template Configuration Properties

  • template defines the base syslog header which will be included for all messages of the data type

    Note: Make sure to include {{extension}} inside the template value in order for the extension template to be rendered as part of the message

  • type_field defines the field in the data that should be used to define which extension should be rendered. The value in the extensions are case sensistive

  • time_format and time_fields provides you the ability to customize the way the timestamps are formatte and which fields to modify. This utilizes python strftime formatting, for more information on strftime formats see https://strftime.org/

Example:

[alerts_template]
template = "{{datetime_utc}} localhost CEF:1|{{vendor}}|{{product}}|{{product_version}}|{{reason_code}}|{{reason}}|{{severity}}|{{extension}}"
type_field = "type"
time_format = "%b %d %Y %H:%m:%S"
time_fields = ["backend_timestamp"]

Extension

  • default defines the extension which will be utilized if no field is specified for type_field or a value was not specified in the extension
  • Any other key in the extension dictionary will be interpretted as a possible value to be matched for the type_field. The values are case sensistive

Example:

[alerts_template.extension]
default = "cat={{type}}\tact={{sensor_action}}\toutcome={{run_state}}"
CB_ANALYTICS = "cat={{type}}\tact={{sensor_action}}\toutcome={{run_state}}\tframeworkName=MITRE_ATT&CK\tthreatAttackID={{attack_tactic}}:{{attack_technique}}"

Fields

The following fields are available for building the Syslog header

  • {{datetime_utc}} - Uses current time with format e.g. 1985-04-12T23:20:50.52Z
  • {{datetime_legacy}} - Uses current time with format e.g. Jan 18 11:07:53
  • {{vendor}} - CarbonBlack
  • {{product}} - CBCSyslog
  • {{product_version}} - Current CBC Syslog version e.g. 2.0.2

For the available Alert fields see Search Fields - Alerts

For the available Audit Log fields see Audit Log Events

Customer Support

If you want to report an issue or request a new feature please open an issue on GitHub

If you are struggling to setup the tool and your an existing Carbon Black Cloud customer reach out to Support from your product console or your sales contact. Support tickets can also be submitted through our User Exchange community.

For other helpful resources check out our contact us page https://developer.carbonblack.com/contact