Fluentd TD-agent 4.0.1 Insecure Folder Permission

`# Exploit Title: Fluentd TD-agent plugin 4.0.1 - Insecure Folder Permission  
# Date: 21.12.2020  
# Exploit Author: Adrian Bondocea  
# Vendor Homepage: https://www.fluentd.org/  
# Software Link: https://td-agent-package-browser.herokuapp.com/4/windows  
# Version: <v4.0.1  
# Tested on: Windows 10 x64  
# CVE : CVE-2020-28169  
# External URL: https://github.com/zubrahzz/FluentD-TD-agent-Exploit-CVE-2020-28169  
  
Description:  
The td-agent-builder plugin before 2020-12-18 for Fluentd allows attackers to gain privileges because the bin directory is writable by a user account, but a file in bin is executed as NT AUTHORITY\SYSTEM.  
  
Vulnerable Path: ( Authenticated Users have permission to write within the location )  
PS C:\opt\td-agent\bin> icacls C:\opt\td-agent\bin  
C:\opt\td-agent\bin BUILTIN\Administrators:(I)(OI)(CI)(F)  
NT AUTHORITY\SYSTEM:(I)(OI)(CI)(F)  
BUILTIN\Users:(I)(OI)(CI)(RX)  
NT AUTHORITY\Authenticated Users:(I)(M)  
NT AUTHORITY\Authenticated Users:(I)(OI)(CI)(IO)(M)  
  
Successfully processed 1 files; Failed processing 0 files  
  
Vulnerable service:  
PS C:\opt\td-agent\bin> get-service fluentdwinsvc  
  
Status Name DisplayName  
------ ---- -----------  
Running fluentdwinsvc Fluentd Windows Service  
  
Service Path:  
"C:/opt/td-agent/bin/ruby.exe" -C t"C:/opt/td-agent/lib/ruby/gems/2.7.0/gems/fluentd-1.11.2/lib/fluent/command/.."  
winsvc.rb --service-name fluentdwinsvc  
  
`