Network Security Memorandum: March 2016

Thursday, March 24, 2016

Cisco IOS Command Tips and Tricks - Part 1

This post is used to collect some small tips and tricks I found during my daily work. Since the list is getting longer and longer, I am splitting it into two posts:

1. Basic Troubleshooting Commands

Ping
Traceroute
Telnet
Show interfaces (show interfaces GigabitEthernet 3/6)
Show ip interface
Show ip route
Show running-config
Show startup-config
show ip sockets
show conn
show tcp brief

2. Archive Command

Configuration Change Logging and Save a copy of current configuration on local when write memory
archive
!!log all commands
log config
logging enable
logging size 200
notify syslog contenttype plaintext
hidekeys
path flash:backup-
maximum 8
write-memory
Compare Startup-Configuration with Running-configuration

R1#show archive config differences
!Contextual Config Diffs:
!No changes were found

show archive log config all
show archive

3. Enable IPv6 on Cisco Switch 3550/3560
3560:
sdm prefer dual-ipv4-and-ipv6 routing

3550:

This link shows how to do it: http://www.cisco.com/en/US/docs/ios-xml/ios/interface/configuration/xe-3s/ip6-ip4-gre-tunls-xe.html

Switch: interface f0/24 is connected to router P1R1

interface FastEthernet0/24

no switchport

ip address 172.17.255.1 255.255.255.254

ip authentication mode eigrp 1 md5

ip authentication key-chain eigrp 1 EIGRP-KEY

ipv6 address 2001:DB8:CAFE:201::/64 eui-64

ipv6 rip 1 enable

spanning-tree portfast

Tunnel 0:

interface Tunnel0

no ip address

ipv6 address 2001:DB8:CAFE:301::/64 eui-64

ipv6 enable

ipv6 rip 1 enable

tunnel source FastEthernet0/24

tunnel destination 172.17.255.0 !---> P1R1

P1R1

interface Tunnel0

no ip address

ipv6 address 2001:DB8:CAFE:301::/64 eui-64

ipv6 enable

ipv6 rip 1 enable

tunnel source Ethernet0/0

tunnel destination 172.17.255.1

4. Using ftp to transfer files to flashcopy ftp://test:test@192.168.2.27 flash:

5. Clear IOS configuraiton

write erase

6. Delete flash: folder

delete /force /recursive flash:/c2960-lanbase-mz.122-52.SE

7. Basic Commands to Enable Telnet/SSH on Cisco Devices

a. Telnet Access

no aaa new-model
username test privilege 15 secret test
line vty 0 15
login local
no password
transport input telnet

b. SSH Access:

hostname Switch1
ip domain-name test.com
crypto key generate rsa general-usage modulus 2048
ip ssh time-out 60
ip ssh version 2
line vty 0 15
transport input ssh

c. Console Access with username/password:

line con 0
login local
exit

8. Debug IP Traffic based on Access-list

The debug procedure is the following:
1) Turn "on" process switching under both interfaces in the router.
Router(config)#interface g0/0
Router(config-if)#no ip route-cache
Router(config)#interface g0/1
Router(config-if)#no ip route-cache

2) Create an access-list. Define specific traffic you want to monitor between hosts.
Router(config)#access-list 199 permit tcp host 11.11.11.1 eq host 22.22.22.2
Router(config)#access-list 199 permit tcp host 22.22.22.2 eq host 11.11.11.1

3) If you are in a telnet session into the router turn "terminal monitor" on.
Router#term mon
If you are in a console session into the router, then the "logging console" command.
Router(config)#logging console

4)Finally the debug command.
Router#debug ip packet 199 detail
Where 199 is the access-list # we created.
*Jul 23 20:25:30.616: IP: s=11.11.11.1 (local), d=22.22.22.2, len 44, local feature, NAT(2), rtype 0, forus FALSE, sendself FALSE, mtu 0, fwdchk FALSE
........

5)Use the "un all" command to turn it off.
Router#un all

9. Kron command

Kron command could use it to reboot router regularly, clear interface, save configuration, show routing table, etc. But it wont support any interactive command.

Following is an example to use it save configuration on a regular basis.

Router# show kron schedule

Kron Occurrence Schedule

backup inactive, will run again in 2 days 22:03:46 at 22:00 on Mon

Router# show running-configuration

(truncated)

kron occurrence backup at 22:00 Mon recurring

policy-list backup

kron policy-list backup

cli write

Another example to run TCL script script.tcl with specific user jonny:kron occurrence tcl_occur user jonny in 12:0 recurring
policy-list tclpol
kron policy-list tclpol
tclsh flash:/script.tcl

10. Enable IP Accounting on interface

IP accounting doesn’t quite provide much functionality, but it certainly provides a summary of traffic passing through a router. The router will only record packets that goes through the router. Any connections initiated from the router or terminates to the router are not counted.

interface GigabitEthernet0/1
ip address 100.199.48.15 255.255.255.0
ip accounting output-packets
duplex full
speed 100
end

R1#sh ip accounting
Source Destination Packets Bytes
100.199.48.10 100.199.3853 6 241
100.199.38.53 100.199.48.10 4 183
138.11.117.16 166.6.23.14 1 104

Accounting data age is 3w0d

11. Show configuration without break/pause @Cisco Router/Switch
terminal length 0

@ASA Firewall
terminal pager 0

12. Debug commands at Cisco ASA 9.1(2)

terminal monitor

logging buffer-size 1048576

logging buffered 7

logging monitor 7

debug crypto condition peer 10.10.10.10

debug crypto ipsec 127
debug crypto ikev1 127

13. Display Cisco IOS Device Opened Ports

R#show control-plane host open-ports
Active internet connections (servers and established)
Prot Local Address Foreign Address Service State
tcp *:22 *:0 SSH-Server LISTEN
tcp *:23 *:0 Telnet LISTEN
udp *:161 *:0 IP SNMP LISTEN
udp *:162 *:0 IP SNMP LISTEN
udp *:65110 *:0 IP SNMP LISTEN
udp *:1975 *:0 IPC LISTEN

The method how to close ports 23 from external scan is in my post: Close Cisco IOS TCP Ports 23, 2002, 4002, 6002, and 9002 from Network Ports Scanning

14. Native VLAN mismatch

062275: May 12 00:09:37.207 EDT: %CDP-4-NATIVE_VLAN_MISMATCH: Native VLAN mismatch discovered on GigabitEthernet0/3 (1), with Swtch1 GigabitEthernet0/5 (56).

although both ports are set as access port and set to different vlan 56 and 1, it should not have this mismatch info. Solution would be one global command :

no cdp advertise-v2

Or

This solution: using different vtp domain name on those switches:

Switch(config)# vtp mode transparent
Switch(config)# vtp domain a_unique_name

15. IOS Password Recovery Procedures

Shut down the router then Power on the router
Press Break on the terminal keyboard within 60 seconds of power up in order to put the router into Rommon. (In some Keyboards, Pause key is used to enter into Rommon mode. You may not need Fn+Pause, or CTRL+ Break)
Once the Rommon1> prompt appears, enter this command: confreg 0x2142
Then type reset to reboot Cisco device.
When you are prompted to enter the initial configuration, type No, and press Enter.
At the Router> prompt, type enable.
At the Router# prompt, enter the configure memory command, and press Enter in order to copy the startup configuration to the running configuration.
Use the config t command in order to enter global configuration mode.
Use this command in order to create a new user name and password:
router(config)#username test privilege 15 password test
Use this command in order to change the boot statement: config-register 0x2102
Use this command in order to save the configuration: write memory

16. Reload Device in xx minutes

It is helpful for your remote work just in case you lost connection by mis-configuration

R-Test-Lab#reload in 1
Reload scheduled for 16:55:53 EDT Tue Aug 11 2015 (in 1 minute) by john on console
Reload reason: Reload Command
Proceed with reload? [confirm]
R-Test-Lab#
***
*** --- SHUTDOWN in 0:01:00 ---
***
R-Test-Lab##show reload
Reload scheduled for 16:55:55 EDT Tue Aug 11 2015 (in 57 seconds) by john on console
Reload reason: Reload Command
R-Test-Lab#reload cancel
R-Test-Lab#
***
*** --- SHUTDOWN ABORTED ---
***

17. Load-Interval 30

By default, the IOS calculate statistics by interval 5 minutes. The minimal interval is 30 seconds you can set.

interface GigabitEthernet0/0
ip flow ingress
load-interval 30
duplex auto
speed auto
end

Router#sh interfaces g0/0
GigabitEthernet0/0 is up, line protocol is up
Hardware is PQ3_TSEC, address is c464.139b.ee00 (bia c464.139b.ee00)
Description:
Internet address is
MTU 1500 bytes, BW 1000000 Kbit/sec, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 3/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Full Duplex, 1Gbps, media type is RJ45
output flow-control is XON, input flow-control is XON
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:00:00, output 00:00:00, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/149/0 (size/max/drops/flushes); Total output drops: 15
Queueing strategy: fifo
Output queue: 0/40 (size/max)
30 second input rate 12706000 bits/sec, 1423 packets/sec 30 second output rate 966000 bits/sec, 957 packets/sec 7877466781 packets input, 4315500899841 bytes, 1023 no buffer
Received 345354184 broadcasts (0 IP multicasts)
0 runts, 0 giants, 13 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 520835 multicast, 2112 pause input
7120190572 packets output, 2103538386166 bytes, 0 underruns
0 output errors, 0 collisions, 0 interface resets
121793930 unknown protocol drops
0 babbles, 0 late collision, 0 deferred
4 lost carrier, 0 no carrier, 58519 pause output
0 output buffer failures, 0 output buffers swapped out

18. Turn off IP Spoof Protection

ip verify reverse-path interface outside
"Deny IP spoof from (10.245.6.1) to 192.168.6.25 on interface inside"

19. Create Read only Account

method one.

username local1 secret Cisco1234
username local1 privilege 15 autocommand show running

aaa new-model
aaa authentication login default local
aaa authorization exec default local
aaa authorization console

method two.

aaa new-model
aaa authentication login default local
aaa authorization exec default local
aaa authorization console

username local2 privilege 7 password Cisco1234
privilege exec level 7 show config

20. Upgrade Cisco Device IOS

Switch# delete /f /r flash1:c3750-ipbase-mz.122.35-35.SE5.bin

Switch#copy tftp: flash:ios.tar

Switch#verify /md5 flash:ios.tar
.........................Done!
verify /md5 (flash:ios.tar) = bb86b1de4eb8e37fd0710c40d891445c

Switch#archive tar /xtract ios.tar flash:

Switch(config)#boot system flash:/ios/ios.bin

Switch#wr
Switch#show boot
BOOT path-list : flash:/ios/ios.bin
Config file : flash:/config.text
Private Config file : flash:/private-config.text
.....

Switch#reload

The list is getting longer , and I am splitting it to two posts:

Reference:

Mobile Iron Sentry VM Installation

What is Mobile Iron Sentry?

Mobile Iron Centry provides access control for email. Sentry connects to Microsoft ActiveSync-enabled email systems such as Microsoft Exchange, IBM Lotus Notes, Google Gmail, and Microsoft Office 365. MobileIron Sentry is an in-line gateway that manages, encrypts, and secures traffic between the mobile device and back-end enterprise systems. Like the VSP, it may be deployed as a physical hardware appliance or a virtual appliance using VMware ESX. Mobile Iron Sentry is included in the Mobile Iron Advanced Management package, though the hardware appliance is sold separately.

MobileIron's Mobile@Work App connects your Android device to your company network so that you can easily and securely access email and other work resources. Mobile@Work App works in conjunction with a MobileIron Core server deployed by your company’s IT organization. .

In this post, I am using sentry-mobileiron-7.0.1-29.iso to do installation into Vmware Workstation 10.

Choose vm-install since I am using virtual machine installation:

Follow the screen instruction, step by step to provide all information:

login as: admin
admin@192.168.236.101's password:
************************************************************
* MobileIron Sentry CLI *
* *
* *
************************************************************
Welcome admin it is Thu Mar 24 16:09:29 UTC 2016

sentry@setry.test.com> enable
Password:
sentry@setry.test.com# ?

clear Reset functions
configure Enter configuration mode
curl Allows you to run curl operation
disable Turn off privilized commands
end Exit from privilige context
exit Exit from the EXEC
help Description of the interactive help system
host Query Internet name servers
install Install tools or rpms
logout Exit from the EXEC
no Negate a command or set to its defaults
ping Send echo messages
poweroff Power off the system.
reload Halt and perform a cold restart
service Allows you do service operations
setup Run the SETUP command facility
show Show running system information
software Check for updates or update software
ssh Open a ssh connection
telnet Open a telnet connection
timeout CLI Idle timeout.
traceroute Trace route to destination

write Save configuration

sentry@setry.test.com# show
banner clock fips hostname interfaces ip kparams log logging logtail memory ntp processes registration running-config

sentry service software statichost system tcp tech timeout version

sentry@setry.test.com# show running-config
Display running configuration
interface GigabitEthernet 1
ip address 192.168.236.101 255.255.255.0
no shutdown
end
interface GigabitEthernet 2
no ip address
shutdown
end
interface GigabitEthernet 3
no ip address
shutdown
end
interface GigabitEthernet 4
no ip address
shutdown
end
ip route 0.0.0.0 0.0.0.0 192.168.236.1
no dbconfig
service ssh 5
service telnet 5
no service ntp
service iptables enable
ip name-server 8.8.8.8 0
ip name-server 8.8.4.4 1
ip domain-name test.com
hostname setry.test.com
timeout 0
system user admin ***
sentry@setry.test.com#
sentry@setry.test.com# reload

System configuration may have been modified. Save? [yes/no]: yes

Configuration saved.

Proceed with reload? [yes/no]: yes

Broadcast message from root (pts/0) (Thu Mar 24 17:58:05 2016):

The system is going down for reboot NOW!

After reboot, you should be able to access https://192.168.236.101:8443 GUI interface. You will have to reboot once after the configuration to enable GUI access.

Sunday, March 20, 2016

Ransomware Locked Files on My Test Machine

One of my test machines which I am using to download and test software from Internet was hit by Ransomware recently.

Check out what it did to my machine.

In most computer folders including c driver and d driver, even on the desktop, there are three following files which obviously is from hackers who is asking for money to decrypt your files.:

+REcovER+gdqvd+.txt
+REcovER+gdqvd+.html
+REcovER+gdqvd+.png

Here is full content from txt file +REcovER+gdqvd+.txt
"

NOT YOUR LANGUAGE? USE https://translate.google.com

What's the matter with your files?

Your data was secured using a strong encryption with RSA4096.
Use the link down below to find additional information on the encryption keys using RSA4096:https://en.wikipedia.org/wiki/RSA_(cryptosystem)

What exactly that means?

It means that on a structural level your files have been transformed. You won't be able to use, read, see or work with them anymore.
In other words they are useless, however, there is a possibility to restore them with our help.

What exactly happened to your files?

*** Two personal RSA4096 keys were generated for your PC/Laptop; one key is public, another key is private.
*** All your data and files were encrypted by the means of the public key, which you received over the web.
*** In order to decrypt your data and gain access to your computer you need a private key and a decryption software, which can be found on one of our secret servers.

What should you do next?

There are several options for you to consider:
1. You can wait for a while until the price of a private key will raise, so you will have to pay twice as much to access your files or
2. You can start getting BitCoins right now and get access to your data quite fast.
In case you have valuable files, we advise you to act fast as there is no other option rather than paying in order to get back your data.

In order to obtain specific instructions, please access your personal homepage by choosing one of the few addresses down below:
http://irudhkunrlfu25fhkaqw34blr5qlby4tgq43t.orrisbirth.com/DE355220943297
http://74nfnjhlq45nkgws4hbdbk45wekfjhqw4talefgnv.curryfort.at/DE355220943297
http://g4dhhg53jsdjnnkjwjrfyiouh3o4u4th.vinerteen.com/DE355220943297

If you can't access your personal homepage or the addresses are not working, complete the following steps:
1 Download TOR Browser - http://www.torproject.org/projects/torbrowser.html.en
2 Install TOR Browser
3 Open TOR Browser
4 Insert the following link in the address bar: k7tlx3ghr3m4n2tu.onion/DE355220943297
5 Follow the instructions on your screen

IMPORTANT INFORMATION

Your personal homepages:
http://irudhkunrlfu25fhkaqw34blr5qlby4tgq43t.orrisbirth.com/DE355220943297
http://74nfnjhlq45nkgws4hbdbk45wekfjhqw4talefgnv.curryfort.at/DE355220943297
http://g4dhhg53jsdjnnkjwjrfyiouh3o4u4th.vinerteen.com/DE355220943297

Your personal page Tor-Browser k7tlx3ghr3m4n2tu.onion/DE355220943297
Your personal identification ID: DE355220943297

Good thing is this computer is only used as a test machine. Nothing lost in this case. I am going to figure out more how to clean it up and post here.

Based on suggestion from google search result listing in my reference link, I downloaded Malwarebytes Anti-Malware to have it a try. After a simple click to install software, a threat scan completed in less than 10 minutes and found 11 potential threats which includes Trojan.Crypt malware under my documents folder.

After a reboot, a follow up scanning will make sure your compute is clean:

Note: After 14 days trial for premium version, it will change to free version and you will lose scheduled scanning and real-time protection.

Reference:

Remove “Your personal files are encrypted” virus (Guide)

Tuesday, March 8, 2016

How Firewalls (Security Gateways) Handle the Packets? (Traffic Flow)

Different firewall (security gateway) vendor has different solution to handle the passing traffic. This post compiles some useful Internet posts that interpret major vendors' solutions including:
1. Checkpoint
2. Palo Alto
3. Fortigate
4. Cisco
5. Juniper
6. F5

1. Checkpoint Firewall Packets Flow:

Here is official Check Point R77 Packet Flow Diagram from sk116255 updated April 2017:

(Source: How to use fw monitor 10-Jul-2003)

Note: Checkpoint can define destination NAT happens at client side (default) or server side. Source NAT always at outbound, and ACL is checked before NAT. More details are on SK85460

Also you could check the packet inspection order/chain through gateway command line.(It will be different based on your enabled features):

1.1 FW-CP1> fw ctl chain

in chain (18):
0: -7f800000 (f28854f0) (ffffffff) IP Options Strip (in) (ipopt_strip)
1: -7d000000 (f1796f10) (00000003) vpn multik forward in
2: - 2000000 (f177cb70) (00000003) vpn decrypt (vpn)
3: - 1fffff8 (f1787c00) (00000001) l2tp inbound (l2tp)
4: - 1fffff6 (f2886ca0) (00000001) Stateless verifications (in) (asm)
5: - 1fffff5 (f28bce30) (00000001) fw multik misc proto forwarding
6: - 1fffff2 (f17a4df0) (00000003) vpn tagging inbound (tagging)
7: - 1fffff0 (f177a150) (00000003) vpn decrypt verify (vpn_ver)
8: - 1000000 (f29049c0) (00000003) SecureXL conn sync (secxl_sync)
9: 0 (f282f810) (00000001) fw VM inbound (fw)
10: 1 (f28a6b30) (00000002) wire VM inbound (wire_vm)
11: 2000000 (f177b5e0) (00000003) vpn policy inbound (vpn_pol)
12: 10000000 (f2902cb0) (00000003) SecureXL inbound (secxl)
13: 7f600000 (f287ab70) (00000001) fw SCV inbound (scv)
14: 7f730000 (f2a13500) (00000001) passive streaming (in) (pass_str)
15: 7f750000 (f2c0bef0) (00000001) TCP streaming (in) (cpas)
16: 7f800000 (f2885890) (ffffffff) IP Options Restore (in) (ipopt_res)
17: 7fb00000 (f2fac050) (00000001) HA Forwarding (ha_for)
out chain (15):
0: -7f800000 (f28854f0) (ffffffff) IP Options Strip (out) (ipopt_strip)
1: -78000000 (f1796ef0) (00000003) vpn multik forward out
2: - 1ffffff (f1779a10) (00000003) vpn nat outbound (vpn_nat)
3: - 1fffff0 (f2c0bd70) (00000001) TCP streaming (out) (cpas)
4: - 1ffff50 (f2a13500) (00000001) passive streaming (out) (pass_str)
5: - 1ff0000 (f17a4df0) (00000003) vpn tagging outbound (tagging)
6: - 1f00000 (f2886ca0) (00000001) Stateless verifications (out) (asm)
7: 0 (f282f810) (00000001) fw VM outbound (fw)
8: 1 (f28a6b30) (00000002) wire VM outbound (wire_vm)
9: 2000000 (f1779c30) (00000003) vpn policy outbound (vpn_pol)
10: 10000000 (f2902cb0) (00000003) SecureXL outbound (secxl)
11: 1ffffff0 (f17887b0) (00000001) l2tp outbound (l2tp)
12: 20000000 (f177d5b0) (00000003) vpn encrypt (vpn)
13: 7f700000 (f2c0e340) (00000001) TCP streaming post VM (cpas)
14: 7f800000 (f2885890) (ffffffff) IP Options Restore (out) (ipopt_res)

1.2 Checkpoint Example for Client Side NAT flow:

The packet that was sent to Server's NATed IP 172.16.0.100, arrives on the "Source/Client" side at the inbound interface eth0 of the Security Gateway (Pre-Inbound chains).
The packet passes the Security Policy rules (inside Virtual Machine).
If accepted, the connection is recorded in the Connections Table (Table ID 8158).
The packet is matched against NAT rules for the Destination. The packet is translated if a match is found - in this case, from IP 172.16.0.100 to IP 10.0.0.100.
The packet passes additional inspection (Post-Inbound chains).
The packet arrives at the TCP/IP stack of the underlying operating system, and is routed to the outbound interface eth1.
The packet goes through the outbound interface eth1 (Pre-Outbound chains).
The packet passes the Security Policy rules (inside Virtual Machine).
The packet is matched against NAT rules for the Source (if such rules exist). The packet is translated if a match is found - in this case, no translation occurs.
The packet passes additional inspection (Post-Outbound chains).
The packet leaves the Security Gateway machine.

1.3 Checkpoint Policy Installation Flow from FW Knowledge Blog:

2. Fortigate FortiOS:

2.1 Packet flow Process:

2.2 Example for Client/server connection:

More packet flow examples can be get from FortiOS Handbook - Troubleshooting PDF file.

3. Palo Alto Traffic Flow:

Flow Logic of the Next-Generation Firewall

4. Cisco IOS/ASA Traffic Flow:

There are more details regarding NAT order, ACL order etc from my previous post: Cisco IOS/ASA Packet Passing Order of Operation

5. JunOS Traffic Flow:

JunOS Flow Module

Next diagram with more details:

6. F5

Thanks Amaud suggestion for F5 TCP Traffic Diagram:

TMOS Order of Operations - TCP Traffic Path Diagram

New version from F5 TCP Traffic Path Diagram Page - December 2015:

F5 LTM Traffic Flow

Following F5 architecture diagram is from Sinso's Post:

Reference:

Monday, March 7, 2016

Check Point R80 Management Installation - Part 2 - SmartConsole

In "Check Point R80 Management Installation - Part 1 - Basic Installation", we can see the steps for installing R80 is similar as previous version. This pose will present how to use SmartConsole to connect to R80 management server.

1. Download SmartConsole

You will get a 378M SmartConsole.exe execute file.

2. Prerequisites for Installing SmartConsole
Double click the download SmartConsole file to start the installation. It will require at least four prerequisites: