Detection rules › Sigma
Third Party Software DLL Sideloading
Detects DLL sideloading of DLLs that are part of third party software (zoom, discord....etc)
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Execution | |
| Stealth |
Telemetry coverage
| Provider | Record / event type |
|---|---|
| Sysmon | Event ID 7: Image loaded |
Rule body
title: Third Party Software DLL Sideloading
id: f9df325d-d7bc-4a32-8a1a-2cc61dcefc63
status: test
description: Detects DLL sideloading of DLLs that are part of third party software (zoom, discord....etc)
references:
- https://hijacklibs.net/ # For list of DLLs that could be sideloaded (search for dlls mentioned here in there)
author: Nasreddine Bencherchali (Nextron Systems), Wietze Beukema (project and research)
date: 2022-08-17
tags:
- attack.persistence
- attack.privilege-escalation
- attack.execution
- attack.stealth
- attack.t1574.001
logsource:
category: image_load
product: windows
detection:
# Lenovo
selection_lenovo:
ImageLoaded|endswith: '\commfunc.dll'
filter_lenovo:
- ImageLoaded|contains: '\AppData\local\Google\Chrome\Application\'
- ImageLoaded|startswith:
- 'C:\Program Files\Lenovo\Communications Utility\'
- 'C:\Program Files (x86)\Lenovo\Communications Utility\'
# Toshiba
selection_toshiba:
ImageLoaded|endswith: '\tosbtkbd.dll'
filter_toshiba:
ImageLoaded|startswith:
- 'C:\Program Files\Toshiba\Bluetooth Toshiba Stack\'
- 'C:\Program Files (x86)\Toshiba\Bluetooth Toshiba Stack\'
# Zoom (FP with System32)
# selection_zoom:
# ImageLoaded|endswith: '\version.dll'
# filter_zoom:
# ImageLoaded|startswith: 'C:\Users\'
# ImageLoaded|contains: '\AppData\Roaming\Zoom\bin\'
condition: (selection_lenovo and not filter_lenovo) or (selection_toshiba and not filter_toshiba)
falsepositives:
- Unknown
level: medium
Stages and Predicates
Stage 0: condition
(selection_lenovo and not filter_lenovo) or (selection_toshiba and not filter_toshiba)Stage 1: selection_lenovo
selection_lenovo:
ImageLoaded|endswith: '\commfunc.dll'
Stage 2: not filter_lenovo
filter_lenovo:
- ImageLoaded|contains: '\AppData\local\Google\Chrome\Application\'
- ImageLoaded|startswith:
- 'C:\Program Files\Lenovo\Communications Utility\'
- 'C:\Program Files (x86)\Lenovo\Communications Utility\'
Stage 3: selection_toshiba
selection_toshiba:
ImageLoaded|endswith: '\tosbtkbd.dll'
Stage 4: not filter_toshiba
filter_toshiba:
ImageLoaded|startswith:
- 'C:\Program Files\Toshiba\Bluetooth Toshiba Stack\'
- 'C:\Program Files (x86)\Toshiba\Bluetooth Toshiba Stack\'
Exclusions
The rule actively suppresses these predicates.
| Field | Kind | Excluded values | Search |
|---|---|---|---|
ImageLoaded | match | \AppData\local\Google\Chrome\Application\ | excludes:ImageLoaded field:"ImageLoaded" value:"\AppData\local\Google\Chrome\Application\" |
ImageLoaded | starts_with | C:\Program Files (x86)\Lenovo\Communications Utility\ | excludes:ImageLoaded field:"ImageLoaded" value:"C:\Program Files (x86)\Lenovo\Communications Utility\" |
ImageLoaded | starts_with | C:\Program Files\Lenovo\Communications Utility\ | excludes:ImageLoaded field:"ImageLoaded" value:"C:\Program Files\Lenovo\Communications Utility\" |
ImageLoaded | starts_with | C:\Program Files (x86)\Toshiba\Bluetooth Toshiba Stack\ | excludes:ImageLoaded field:"ImageLoaded" value:"C:\Program Files (x86)\Toshiba\Bluetooth Toshiba Stack\" |
ImageLoaded | starts_with | C:\Program Files\Toshiba\Bluetooth Toshiba Stack\ | excludes:ImageLoaded field:"ImageLoaded" value:"C:\Program Files\Toshiba\Bluetooth Toshiba Stack\" |
Indicators
These rows show field, operator, and value matches.
| Field | Kind | Values | Search |
|---|---|---|---|
ImageLoaded | ends_with |
| field:"ImageLoaded" kind:ends_with |