HackTool - KrbRelay Execution — Sigma Rule

Rule metadata and linked tags

Author: Florian Roth (Nextron Systems). Source status: test; severity: high. Source dates: 2022-04-27 / 2023-02-04.

{
  "category": "process_creation",
  "product": "windows"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: be1b625ee811582df702d77bd85c83dc266df63d7f15204854bce2ea10c21f91

Detection logic

Original source YAML. Source-tag agreement is not proof of complete semantic coverage. This rule has not been compiled for a SIEM backend or validated against live telemetry here.

title: HackTool - KrbRelay Execution
id: e96253b8-6b3b-4f90-9e59-3b24b99cf9b4
status: test
description: Detects the use of KrbRelay, a Kerberos relaying tool
references:
    - https://github.com/cube0x0/KrbRelay
author: Florian Roth (Nextron Systems)
date: 2022-04-27
modified: 2023-02-04
tags:
    - attack.credential-access
    - attack.t1558.003
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - Image|endswith: '\KrbRelay.exe'
        - OriginalFileName: 'KrbRelay.exe' # In case the file has been renamed after compilation
    selection_cli_1:
        CommandLine|contains|all:
            - ' -spn '
            - ' -clsid '
            - ' -rbcd '
    selection_cli_2:
        CommandLine|contains|all:
            - 'shadowcred'
            - 'clsid'
            - 'spn'
    selection_cli_3:
        CommandLine|contains|all:
            - 'spn '
            - 'session '
            - 'clsid '
    condition: 1 of selection_*
falsepositives:
    - Unlikely
level: high

Original YAML and metadata in JSON

False positives

• Unlikely

Source references

• https://github.com/cube0x0/KrbRelay