PowerShell ScriptBlock Requesting Kerberos Tickets via System.IdentityModel.Tokens.KerberosRequestorSecurityToken
Alerts on PowerShell ScriptBlock text that builds Kerberos ticket requests using KerberosRequestorSecurityToken and .GetRequest().
- Product
- windows
- Category
- ps_script
- Author
- frack113 (SigmaHQ), DRL 1.1
- Published
- 2021-12-28
- Updated
- 2026-10-03
ATT&CK techniques
Cred AccessRecon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact
What it detects
This rule flags PowerShell ScriptBlock content that references the .NET KerberosRequestorSecurityToken constructor to request Kerberos tickets. Such ticket requests can support credential access activity where tickets are later cached and may be targeted by other tooling. Detection relies on PowerShell Script Block Logging telemetry capturing the referenced .NET type in the script text.
Reporting behind it
- github.comhttps://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1558.003/T1558.003.md#atomic-test-4---request-a-single-ticket-via-powershell
- learn.microsoft.comhttps://learn.microsoft.com/en-us/dotnet/api/system.identitymodel.tokens.kerberosrequestorsecuritytoken?view=netframework-4.8.1
- github.comhttps://github.com/SigmaHQ/sigma/blob/master/rules/windows/powershell/powershell_script/posh_ps_request_kerberos_ticket.yml
Changelog
v5- v5Candidate ingested via manual entry.2026-10-03
- v2Candidate ingested via manual entry.2026-07-31
- v1No changelog recorded for this version.2026-07-30
Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.
title: PowerShell ScriptBlock Requesting Kerberos Tickets 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 content that references the .NET KerberosRequestorSecurityToken constructor to request Kerberos tickets. Such ticket requests can support credential access activity where tickets are later cached and may be targeted by other tooling. Detection relies on PowerShell Script Block Logging telemetry capturing the referenced .NET type in the script 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: 2026-09-14
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: System.IdentityModel.Tokens.KerberosRequestorSecurityToken
condition: selection
falsepositives:
- Legitimate Kerberos authentication development and troubleshooting scripts
level: high
regression_tests_path: regression_data/rules/windows/powershell/powershell_script/posh_ps_request_kerberos_ticket/info.yml
license: DRL-1.1