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Nessus 4.2.0 : Web Interface

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Interestingly enough, I found last week that the new Nessus 4.2.0 works by default as a web interface. Gone are the days of using the NessusClient and connecting to TCP port 1241 and using it to connect to the nessusd. Connecting to local TCP port 8834 (https://localhost:8834) brings you to a web interface that you can use to connect to the new Nessus daemon. The nesssusd listener does not even listen on port 1241 by default.
I’ll shortly get used to it but I know the transition would be slow for me …. after it takes getting used to when you completely change the architecture after maintaining it for at least a good 7 years or so!

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Cisco Router Security

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Long time since I posted anything here …. but it’s just been those times been busy as a bee. So securing Cisco routers is a big deal especially since the routers (especially the edge routers) can be critical to any organizations infrastructure. I am not a Cisco guru but am only a student. However, I thought I should create a list that could help me perform security reviews of routers.
Security of routers is important as attackers could add static routes, advertise bad BGP neighbours on edge routers, create inbound tunnel into the intranets and such. Therefore, it’s imperative that adequate efforts be put in to secure Cisco routers.

I thought I’ll put in my first attempt at creating a small checklist:

  1. Use SSH for non-console access (“line vty” command should not have telnet in it)
  2. Use class 5 passwords, do *not* use class 7 passwords as they’re easily reversed (“enable secret”) alongwith the use of strong passez
  3. Limit virtual terminal access by using an ACL
       access-list 100 permit 10.10.10.10 log
       access-list 100 permit 10.10.10.11 log
       access-list deny any log
       line vty 0 4
        access-class 100 in
  4. Disable Proxy ARP on each interface (“no ip proxy arp”)
  5. Disable CDP as it can be used for information disclosures (“no cdp run”)
  6. Use AAA (TACACS+ or RADIUS) (“aaa new-model”, “aaa authentication”, etc.)
  7. Use “access-list ACL_NAME deny ip any any log” at the end of each ACL
  8. Disable http server (“no ip http server”)
  9. Keep the IOS versions updated
  10. Set centralized logging using a syslog (“logging internal_ip_address”)
  11. Configure NTP to keep the time synchronization (“ntp server 129.6.15.28”)
  12. Disable TCP and UDP small services e.g., echo, chargen, discard, etc. (“no service tcp-small-servers” and “no service udp-small-servers”)
  13. Put RFC 1918 (ingress filtering) protections using ACLs
       access-list 100 deny ip 127.0.0.0 0.255.255.255 any log
       access-list 100 deny ip 10.0.0.0 0.255.255.255 any log
       access-list 100 deny ip 192.168.0.0 0.0.255.255 any log
       access-list 100 deny ip 172.16.0.0 0.15.255.255 any log
  14. Put some more filtering for common IPs
       access-list 100 deny ip 169.254.0.0 0.0.255.255 any log
  15. Use SNMPv3 with ACLs if you must (“snmp-server v3 auth priv”)
  16. Use SSHv2 (“ip ssh version 2”)
  17. Try to use EIGRP instead of RIP/OSPF (“ip authentication mode eigrp N md5”)
  18. Use MD5 authentication for RIP/OSPF if you must use these protocols (RIPv2/OSPF)
    (“ip rip authentication mode md5”)
  19. For edge routers using BGP authentication (if possible)
       router bgp 10
        neighbor 10.10.10.10 password Cr4zY$%^
  20. Configure BGP route flap dampening that prevents BGP oscillations (“bgp dampening”)
  21. Use warning banners that could be used for legal purposes for prosecuting hackers