Detection rules › Sigma

Suspicious Kerberos Ticket Request via CLI

Status
experimental
Severity
high
Log source
category process_creation, product windows
Author
Swachchhanda Shrawan Poudel (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects suspicious Kerberos ticket requests via command line using System.IdentityModel.Tokens.KerberosRequestorSecurityToken class. Threat actors may use command line interfaces to request Kerberos tickets for service accounts in order to perform offline password cracking attacks commonly known as Kerberoasting or other Kerberos ticket abuse techniques like silver ticket attacks.

Known false positives

  • Legitimate command line usage by administrators or security tools.

MITRE ATT&CK coverage

Telemetry coverage

ProviderRecord / event type
SysmonEvent ID 1: Process creation

Rule body

title: Suspicious Kerberos Ticket Request via CLI
id: caa9a802-8bd8-4b9e-a5cd-4d6221670219
related:
    - id: a861d835-af37-4930-bcd6-5b178bfb54df
      type: similar
status: experimental
description: |
    Detects suspicious Kerberos ticket requests via command line using System.IdentityModel.Tokens.KerberosRequestorSecurityToken class.
    Threat actors may use command line interfaces to request Kerberos tickets for service accounts in order to
    perform offline password cracking attacks commonly known as Kerberoasting or other Kerberos ticket abuse
    techniques like silver ticket attacks.
references:
    - https://www.huntress.com/blog/gootloader-threat-detection-woff2-obfuscation
    - 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
author: Swachchhanda Shrawan Poudel (Nextron Systems)
date: 2025-11-18
tags:
    - attack.credential-access
    - attack.t1558.003
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - Image|endswith:
              - '\powershell.exe'
              - '\pwsh.exe'
        - OriginalFileName:
              - 'powershell.exe'
              - 'pwsh.dll'
    selection_cli:
        CommandLine|contains|all:
            - 'System.IdentityModel.Tokens.KerberosRequestorSecurityToken'
            - '.GetRequest()'
    condition: all of selection_*
falsepositives:
    - Legitimate command line usage by administrators or security tools.
level: high

Stages and Predicates

Stage 0: condition

all of selection_*

Stage 1: selection_img

selection_img:
    - Image|endswith:
          - '\powershell.exe'
          - '\pwsh.exe'
    - OriginalFileName:
          - 'powershell.exe'
          - 'pwsh.dll'

Stage 2: selection_cli

selection_cli:
    CommandLine|contains|all:
        - 'System.IdentityModel.Tokens.KerberosRequestorSecurityToken'
        - '.GetRequest()'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
CommandLinematch
  • .GetRequest()
  • System.IdentityModel.Tokens.KerberosRequestorSecurityToken
field:"CommandLine" kind:match
Imageends_with
  • \powershell.exe corpus 179 (sigma 178, kusto 1)
  • \pwsh.exe corpus 165 (sigma 164, kusto 1)
field:"Image" kind:ends_with
OriginalFileNameeq
  • powershell.exe corpus 138 (sigma 84, splunk 30, elastic 24)
  • pwsh.dll corpus 112 (sigma 79, splunk 30, elastic 3)
field:"OriginalFileName" kind:eq