Suspicious GUP Usage — Sigma Rule

Rule metadata and linked tags

Author: Florian Roth (Nextron Systems). Source status: test; severity: high. Source dates: 2019-02-06 / 2022-08-13.

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

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: 58f7f1c972cf58836122827cf77a192d4ed67bd63bf66b140110cf6d426d21bd

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: Suspicious GUP Usage
id: 0a4f6091-223b-41f6-8743-f322ec84930b
status: test
description: Detects execution of the Notepad++ updater in a suspicious directory, which is often used in DLL side-loading attacks
references:
    - https://www.fireeye.com/blog/threat-research/2018/09/apt10-targeting-japanese-corporations-using-updated-ttps.html
author: Florian Roth (Nextron Systems)
date: 2019-02-06
modified: 2022-08-13
tags:
    - attack.privilege-escalation
    - attack.persistence
    - attack.execution
    - attack.stealth
    - attack.t1574.001
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        Image|endswith: '\GUP.exe'
    filter_programfiles:
        Image|endswith:
            - '\Program Files\Notepad++\updater\GUP.exe'
            - '\Program Files (x86)\Notepad++\updater\GUP.exe'
    filter_user:
        Image|contains: '\Users\'
        Image|endswith:
            - '\AppData\Local\Notepad++\updater\GUP.exe'
            - '\AppData\Roaming\Notepad++\updater\GUP.exe'
    condition: selection and not 1 of filter_*
falsepositives:
    - Execution of tools named GUP.exe and located in folders different than Notepad++\updater
level: high

Original YAML and metadata in JSON

False positives

• Execution of tools named GUP.exe and located in folders different than Notepad++\updater

Source references

• https://www.fireeye.com/blog/threat-research/2018/09/apt10-targeting-japanese-corporations-using-updated-ttps.html