Brute Force Investigation - Generic - SANS

This playbook investigates a "Brute Force" incident by gathering user and IP information, and calculating the incident severity based on the gathered information and information received from the user. It then performs remediation. This is done based on the phases for handling an incident as they are described in the SANS Institute ‘Incident Handler’s Handbook’ by Patrick Kral. https://www.sans.org/reading-room/whitepapers/incident/incident-handlers-handbook-33901 The playbook handles the following use-cases: * Brute Force IP Detected - A detection of source IPs that are exceeding a high threshold of rejected and/or invalid logins. * Brute Force Increase Percentage - A detection of large increase percentages in various brute force statistics over different periods of time. * Brute Force Potentially Compromised Accounts - A detection of accounts that have shown high amount of failed logins with one successful login. Used Sub-playbooks: - IP Enrichment - Generic v2 - Account Enrichment - Generic v2.1 - Calculate Severity - Critical Assets v2 - Isolate Endpoint - Generic v2 - Block Indicators - Generic v3 - SANS - Lessons Learned ***Disclaimer: This playbook does not ensure compliance to SANS regulations.

Pack

SANS

Tasks

54

Inputs

• username — Username of the user who is suspected of the activity.
• traps_endpoint_id — Traps endpoint ID, used for endpoint isolation.
• logins_count_threshold — The threshold for number of logins, from which the investigation and remediation will start automatically without waiting for the user's reply. Default is 10.
• severity_threshold — The threshold for the severity value from which an automatic remediation takes place. Specify the severity number (default is Critical): 0 - Unknown 0.5 - Informational 1 - Low 2 - Medium 3 - High 4 - Critical
• internal_range — A list of internal IP ranges to check IP addresses against. The comma-separated list should be provided in CIDR notation. For example, a list of ranges would be: "172.16.0.0/12,10.0.0.0/8,192.168.0.0/16" (without quotes).
• critical_users — Critical users, separated by comma.
• critical_endpoints — Critical endpoints, separated by comma.
• critical_groups — Critical groups, separated by comma.
• CustomBlockRule — This input determines whether Palo Alto Networks Panorama or Firewall Custom Block Rules are used. Specify True to use Custom Block Rules.
• AutoCommit — This input determines whether Palo Alto Networks Panorama or Firewall Static Address Groups are used. Specify the Static Address Group name for IP handling.
• DAG — This input determines whether Palo Alto Networks Panorama or Firewall Dynamic Address Groups are used. Specify the Dynamic Address Group tag name for IP handling.
• StaticAddressGroup — This input determines whether Palo Alto Networks Panorama or Firewall Static Address Groups are used. Specify the Static Address Group name for IP handling.
• CustomURLCategory — Custom URL Category name.
• type — Custom URL category type. Insert "URL List"/ "Category Match".
• device-group — Device group for the Custom URL Category (Panorama instances).
• categories — The list of categories. Relevant from PAN-OS v9.x.
• EDLServerIP — This input determines whether Palo Alto Networks Panorama or Firewall External Dynamic Lists are used: * The IP address of the web server on which the files are stored. * The web server IP address is configured in the integration instance.
• UserVerification — Possible values: True/False. Whether to provide user verification for blocking IPs. False - No prompt will be displayed to the user. True - The server will ask the user for blocking verification and will display the blocking list.
• AutoBlockIndicators — Possible values: True/False. Default: True. Should the given indicators be automatically blocked, or should the user be given the option to choose? If set to True - no prompt will appear, and all provided indicators will be blocked automatically. If set to False - the user will be prompted to select which indicators to block.
• Email — Email address to which to send the questions.
• DataCollection — Use a data collection task to answer lessons learned questions based on SANS. Specify 'True' to automatically send the communication task, and 'False' to prevent it.

Commands used

• ad-disable-account
• ad-enable-account
• ad-expire-password
• closeInvestigation
• send-mail
• setIncident