HackTool - KrbRelayUp Execution — Sigma Rule

Rule metadata and linked tags

Author: Florian Roth (Nextron Systems). Source status: test; severity: high. Source dates: 2022-04-26 / 2023-02-04.

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

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: b372fd00467c5660b8060a415bed56f0c764bfbcdff387463cff9c846359505e

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 - KrbRelayUp Execution
id: 12827a56-61a4-476a-a9cb-f3068f191073
status: test
description: Detects KrbRelayUp used to perform a universal no-fix local privilege escalation in Windows domain environments where LDAP signing is not enforced
references:
    - https://github.com/Dec0ne/KrbRelayUp
author: Florian Roth (Nextron Systems)
date: 2022-04-26
modified: 2023-02-04
tags:
    - attack.credential-access
    - attack.t1558.003
    - attack.lateral-movement
    - attack.t1550.003
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - Image|endswith: '\KrbRelayUp.exe'
        - OriginalFileName: 'KrbRelayUp.exe' # In case the file has been renamed after compilation
    selection_cli_1:
        CommandLine|contains|all:
            - ' relay '
            - ' -Domain '
            - ' -ComputerName '
    selection_cli_2:
        CommandLine|contains|all:
            - ' krbscm '
            - ' -sc '
    selection_cli_3:
        CommandLine|contains|all:
            - ' spawn '
            - ' -d '
            - ' -cn '
            - ' -cp '
    condition: 1 of selection_*
falsepositives:
    - Unlikely
level: high

Original YAML and metadata in JSON

False positives

• Unlikely

Source references

• https://github.com/Dec0ne/KrbRelayUp