PowerShell ScriptBlock Kerberos Ticket Requests via System.IdentityModel.Tokens.KerberosRequestorSecurityToken

title: PowerShell ScriptBlock Kerberos Ticket Requests via System.IdentityModel.Tokens.KerberosRequestorSecurityToken
id: e5019227-acf0-4772-b82b-d8e8689a1cbe
related:
  - id: caa9a802-8bd8-4b9e-a5cd-4d6221670219
    type: similar
  - id: a861d835-af37-4930-bcd6-5b178bfb54df
    type: derived
status: test
description: This rule flags PowerShell ScriptBlock activity containing both System.IdentityModel.Tokens.KerberosRequestorSecurityToken and a .GetRequest() call, indicating a Kerberos ticket request being constructed in script. Such behavior matters because scripted Kerberos ticket acquisition can be used to access services or facilitate credential-based attacks. Detection relies on Script Block logging telemetry that records the PowerShell ScriptBlock text.
references:
  - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1558.003/T1558.003.md#atomic-test-4---request-a-single-ticket-via-powershell
  - https://learn.microsoft.com/en-us/dotnet/api/system.identitymodel.tokens.kerberosrequestorsecuritytoken?view=netframework-4.8.1
  - https://github.com/SigmaHQ/sigma/blob/master/rules/windows/powershell/powershell_script/posh_ps_request_kerberos_ticket.yml
author: frack113, Huntrule Team
date: 2021-12-28
modified: 2025-11-18
tags:
  - attack.credential-access
  - attack.t1558.003
logsource:
  product: windows
  category: ps_script
  definition: "Requirements: Script Block Logging must be enabled"
detection:
  selection:
    ScriptBlockText|contains|all:
      - System.IdentityModel.Tokens.KerberosRequestorSecurityToken
      - .GetRequest()
  condition: selection
falsepositives:
  - Unknown
level: high
license: DRL-1.1