Detection rules › Sigma

Arbitrary Binary Execution Using GUP Utility

Status
test
Severity
medium
Log source
category process_creation, product windows
Author
Nasreddine Bencherchali (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects execution of the Notepad++ updater (gup) to launch other commands or executables

Known false positives

  • Other parent binaries using GUP not currently identified

MITRE ATT&CK coverage

TacticTechniques
ExecutionNo specific technique

Telemetry coverage

Rule body

title: Arbitrary Binary Execution Using GUP Utility
id: d65aee4d-2292-4cea-b832-83accd6cfa43
status: test
description: Detects execution of the Notepad++ updater (gup) to launch other commands or executables
references:
    - https://twitter.com/nas_bench/status/1535322445439180803
author: Nasreddine Bencherchali (Nextron Systems)
date: 2022-06-10
modified: 2023-03-02
tags:
    - attack.execution
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        ParentImage|endswith: '\gup.exe'
        Image|endswith: '\explorer.exe'
    filter:
        Image|endswith: '\explorer.exe'
        CommandLine|contains: '\Notepad++\notepad++.exe'
    filter_parent:
        ParentImage|contains: '\Notepad++\updater\'
    filter_null:
        CommandLine: null
    condition: selection and not 1 of filter*
falsepositives:
    - Other parent binaries using GUP not currently identified
level: medium

Stages and Predicates

Stage 0: condition

selection and not 1 of filter*

Stage 1: selection

selection:
    ParentImage|endswith: '\gup.exe'
    Image|endswith: '\explorer.exe'

Stage 2: not filter*

filter:
    Image|endswith: '\explorer.exe'
    CommandLine|contains: '\Notepad++\notepad++.exe'
filter_parent:
    ParentImage|contains: '\Notepad++\updater\'
filter_null:
    CommandLine: null

Exclusions

The rule actively suppresses these predicates.

FieldKindExcluded valuesSearch
CommandLinematch\Notepad++\notepad++.exeexcludes:CommandLine field:"CommandLine" value:"\Notepad++\notepad++.exe"
Imageends_with\explorer.exeexcludes:Image field:"Image" value:"\explorer.exe"
CommandLineis_null(no value, null check)excludes:CommandLine
ParentImagematch\Notepad++\updater\excludes:ParentImage field:"ParentImage" value:"\Notepad++\updater\"

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
Imageends_with
  • \explorer.exe corpus 13 (sigma 13)
field:"Image" kind:ends_with value:"\explorer.exe"
ParentImageends_with
  • \gup.exe corpus 2 (sigma 2)
field:"ParentImage" kind:ends_with value:"\gup.exe"