Configuring IPS Blocking Using IME

Introduction

This document discusses the configuration of the Intrusion Prevention System (IPS) blocking with the use of the IPS Manager Express (IME). IME and IPS Sensors are used to manage a Cisco router for blocking. Remember these items when you consider this configuration:

• Install the Sensor and make sure the Sensor works properly.

• Make the sniffing interface span to the router outside the interface.

Prerequisites

Requirements

There are no specific requirements for this document.

Components Used

The information in this document is based on these software and hardware versions:

• Cisco IPS Manager Express 7.0

• Cisco IPS Sensor 7.0(0.88)E3

• Cisco IOS^® router with Cisco IOS Software Release 12.4

The information in this document was created from the devices in a specific lab environment. All of the devices used in this document started with a cleared (default) configuration. If your network is live, make sure that you understand the potential impact of any command.

Conventions

Refer to the Cisco Technical Tips Conventions for more information on document conventions.

Configure

Network Diagram

This document uses this network setup.

Configurations

This document uses these configurations.

• Router Light

• Router House

Current configuration : 906 bytes
!
version 12.4
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname light
!
enable password cisco
!
username cisco password 0 cisco
ip subnet-zero
!
!
!
ip ssh time-out 120
ip ssh authentication-retries 3
!
call rsvp-sync
!
!
!
fax interface-type modem
mta receive maximum-recipients 0
!
controller E1 2/0
!
!
!
interface FastEthernet0/0
 ip address 10.100.100.2 255.255.255.0
 duplex auto
 speed auto
!
interface FastEthernet0/1
 ip address 1.1.1.1 255.255.255.0
 duplex auto
 speed auto
!
interface BRI4/0
 no ip address
 shutdown
interface BRI4/1
 no ip address
 shutdown
!
interface BRI4/2
 no ip address
 shutdown
!
interface BRI4/3
 no ip address
 shutdown
!
ip classless
ip route 0.0.0.0 0.0.0.0 10.100.100.1
ip http server
ip pim bidir-enable
!
!
dial-peer cor custom
!
!
line con 0
line 97 108
line aux 0
line vty 0 4
 login
!
end

Current configuration : 939 bytes
!
version 12.4
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname house
!
logging queue-limit 100
enable password cisco
!
ip subnet-zero
!
!
no ip cef
no ip domain lookup
!
ip audit notify log
ip audit po max-events 100
!
!
no voice hpi capture buffer
no voice hpi capture destination
!
!
!
!
interface FastEthernet0/0
 ip address 10.66.79.210 255.255.255.224
 duplex auto
 speed auto
!
interface FastEthernet0/1
 ip address 10.100.100.1 255.255.255.0
 ip access-group IDS_FastEthernet0/1_in_0 in 

!--- After you configure blocking, !--- IDS Sensor inserts this line.

 duplex auto
 speed auto
!
interface ATM1/0
 no ip address
 shutdown
 no atm ilmi-keepalive
!
ip classless
ip route 0.0.0.0 0.0.0.0 10.66.79.193
ip route 1.1.1.0 255.255.255.0 10.100.100.2
no ip http server
no ip http secure-server
!
!
ip access-list extended IDS_FastEthernet0/1_in_0
 permit ip host 10.66.79.195 any
 permit ip any any

!--- After you configure blocking, !--- IDS Sensor inserts this line.

!
call rsvp-sync
!
!
mgcp profile default
!
!
line con 0
 exec-timeout 0 0
line aux 0
line vty 0 4
 exec-timeout 0 0
 password cisco
 login
line vty 5 15
 login
!
!
end

Start the Sensor Configuration

Complete these steps to start the configuration of the Sensor.

1. If this is your first time logging into the Sensor, you must enter cisco as the user name and cisco as the password.

2. When the system prompts you, change your password.

   Note: Cisco123 is a dictionary word and is not allowed in the system.

3. Type setup and follow the system prompt to setup the basic parameters for the Sensors.

4. Enter this information:

   sensor5#setup 
   
       --- System Configuration Dialog --- 
   
   
   !--- At any point you may enter a question mark '?' for help. !--- Use ctrl-c to abort the configuration dialog at any prompt. !--- Default settings are in square brackets '[]'. 
   
   Current time: Thu Oct  22 21:19:51 2009
   
   Setup Configuration last modified:
   
   Enter host name[sensor]:
   Enter IP interface[10.66.79.195/24,10.66.79.193]:
   
   Modify current access list?[no]:
   Current access list entries:
   
   !--- permit the ip address of workstation or network with IME
   
   Permit:10.66.79.0/24
   Permit:
   Modify system clock settings?[no]:
     Modify summer time settings?[no]:
       Use USA SummerTime Defaults?[yes]:
       Recurring, Date or Disable?[Recurring]:
       Start Month[march]:
       Start Week[second]:
       Start Day[sunday]:
       Start Time[02:00:00]:
       End Month[november]:
       End Week[first]:
       End Day[sunday]:
       End Time[02:00:00]:
       DST Zone[]: 
       Offset[60]:
     Modify system timezone?[no]:
       Timezone[UTC]:
       UTC Offset[0]:
     Use NTP?[no]: yes
       NTP Server IP Address[]: 
       Use NTP Authentication?[no]: yes
         NTP Key ID[]: 1
         NTP Key Value[]: 8675309

5. Save the configuration.

   It can take a few minutes for the Sensor to save the configuration.

   [0] Go to the command prompt without saving this config. 
   [1] Return back to the setup without saving this config. 
   [2] Save this configuration and exit setup. 
   
   Enter your selection[2]: 2 

Add the Sensor into the IME

Complete these steps in order to add the Sensor into the IME.

1. Go to the Windows PC, which installed the IPS Manager Express and open the IPS Manager Express.

2. Choose Home > Add.

3. Type in this information and click OK in order to finish the configuration.

   

4. Choose Devices > sensor5 in order to verify the Sensor status and then right-click to choose Status.

   Make sure that you can see the Subscription successfully opened. message.

   

Configure Blocking for the Cisco IOS Router

Complete these steps in order to configure the blocking for the Cisco IOS route:.

1. From the IME PC, open your web browser and go to https://10.66.79.195.

2. Click OK in order to accept the HTTPS certificate downloaded from the Sensor.

3. In the Login window, enter cisco for the user name and 123cisco123 for the password.

   This IME management interface appears:

   

4. From the Configuration tab, click Active Signatures.

5. Then, click Signature Wizard.

   

   Note: The previous screenshot has been cut into two parts because of space limitation.

6. Choose Yes and String TCP as Signature engine. Click Next.

   

7. You can leave this information as Default or enter your own Signature ID, Signature Name and User Notes. Click Next.

   

8. Choose Event Action and choose Produce Alert and Request Block Host. Click Next in order to continue.

   

9. Enter a Regular Expression , which in this example is testattack, enter 23 for Service Ports, choose To Service for the Direction, and click Next in order to continue.

   

10. You can leave this information as Default. Click Next.

    

11. Click Finish in order to finish the Wizard.

    

12. Choose Configuration > sig0 > Active Signatures in order locate the newly created signature by Sig ID or Sig Name. Click Edit in order to view the signature.

    

13. Click OK after you confirm and click the Apply button in order to apply the signature to the Sensor.

14. From the Configuration tab, under Sensor Management click Blocking. From the left pane, choose Blocking Properties and check Enable Blocking.

    

15. Now from the left pane, go to Device Login Profile. In order to create a new profile, click Add. Once created click OK and Apply in order to sensor and continue.

    

16. The next step is to configure Router as Blocking device. From the left pane, choose Blocking Device, click Add in order to add this information. Then click OK and Apply.

    

17. Now from the left pane configure the Blocking device interfaces. Add the information, click OK and Apply..

    

Verify

Launch the Attack and Blocking

Complete these steps to launch the attack and blocking:

1. Before you launch the attack, go to the IME, choose Event Monitoring > Dropped Attacks View and choose the sensor on the right.

2. Telnet to Router House and verify the communication from the server with these commands.

   house#show user
    
     Line     User      Host(s)          Idle        Location
   * 0 con 0             idle          00:00:00
   226 vty 0             idle          00:00:17     10.66.79.195
   
   
   house#show access-list
   Extended IP access list IDS_FastEthernet0/1_in_0
     permit ip host 10.66.79.195 any
     permit ip any any (12 matches)
   house#

3. From Router Light, Telnet to Router House and type testattack.

   Hit either <space> or <enter> in order to reset your Telnet session.

   light#telnet 10.100.100.1 
       Trying 10.100.100.1 ... Open 
   
       User Access Verification 
       Password: 
       house>en 
       Password: 
       house#testattack 
       [Connection to 10.100.100.1 lost] 
       
   !--- Host 10.100.100.2 has been blocked due to the !--- signature "testattack" triggered. 
   
   

4. Telnet to Router House and use the show access-list command as shown here.

   house#show access-list 
   Extended IP access list IDS_FastEthernet0/1_in_0
   10 permit ip host 10.66.79.195 any 
   20 deny ip host 10.100.100.2 any (71 matches) 
   30 permit ip any any 

5. From the Dashboard of the IDS Event Viewer, the Red Alarm appears once the attack is launched.

   

Troubleshoot

This section provides information you can use to troubleshoot your configuration.

Tips

Use these troubleshooting tips:

• From the Sensor look at the show statistics network-access output and make sure that the state"is active. From the console or SSH to the Sensor, this information is viewed:

  sensor5#show statistics network-access 
  Current Configuration
    AllowSensorShun = false
    ShunMaxEntries = 100
    NetDevice
      Type = Cisco
      IP = 10.66.79.210
      NATAddr = 0.0.0.0
      Communications = telnet
      ShunInterface
        InterfaceName = FastEthernet0/1
        InterfaceDirection = in
  State
    ShunEnable = true
    NetDevice
      IP = 10.66.79.210
      AclSupport = uses Named ACLs
      State = Active
    ShunnedAddr
      Host
        IP = 10.100.100.2
        ShunMinutes = 15
        MinutesRemaining = 12
  sensor5#

• Make sure the communication parameter shows that the correct protocol is used such as Telnet or SSH with 3DES. You can try a manual SSH or Telnet from an SSH/Telnet client on a PC in order to check the username and password credentials are correct. Then try to Telnet or SSH from the Sensor itself to the router and see if you can login successfully to the router.

Related Information

• Cisco Secure Intrusion Prevention Support Page
• Technical Support & Documentation - Cisco Systems