Securing Against Internal Network Threats with IPTABLES
How to use iptables to secure your network against internal threats with PacketFence, a transparent Linux bridge and a bit of custom PHP scripting.
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Configuring a Transparent Bridge in Ubuntu
Configuring a transparent pseudo-bridge, proxy-arp and routing multiple network cards with Ubuntu for added security and flexibility.
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Using a RADIUS Server on Ubuntu 14.04 for WIFI Authentication
WPA2 Enterprise is the much more secure wifi authentication method. There's no hackers cracking login passwords if you do this, but there are a few downsides. Here's how to implement it for a small environment.
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Linux, iptables, SNAT and Too Many Adapters
I've had some weird glitches with my primary firewall this week. After a reboot, certain SNAT rules just didn't... happen. Or, other SNAT rules did. And it always seemed to only impact SIP traffic. For instance, after rebooting, SIP traffic from one internal phone server that's destined for another internal phone server at the other end of a VPN connection would spontaneously decide to SNAT itself to an external IP address, yet still go across the tunnel. Or, SIP traffic destined for the outside would decide to route correctly out the right adapter, but leave the private address on it, ignoring the SNAT rule I could plainly see in iptables.
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The Pentagon Demonstrates How Ignorant They Are
A recent article in the New York Times demonstrates just how helpless our nation is against hacker threats. Please notice my lack of using the word "Cyber" which in reality has nothing to do with the Internet or computer security, despite the media's attention to the word.
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Password Security (and Why You Should Be Trembling)
No doubt by now you know that Sony's Playstation network was hacked. The attackers got away with the user database, and probably with credit card information as well. I'm going to get a little technical today and talk about passwords.
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LDAP Authentication with TLS
I've been using LDAP for central authentication, but I hadn't added encryption until recently. With the advent of network switches, on a cabled network it has become very difficult to "sniff" or listen in on other network traffic. With wireless though it's much easier, so encrypting all traffic is a good idea.
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IPTables Trickery
I've had a bit of a strange situation on my network - Googling never did come up with anything for me.
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Stop Port Scans In Their Tracks With iptables
Sure, there's a lot of tutorials out there for blocking SYN+FIN, christmas scans, etc. But did you know that most of those won't help against a default nmap scan? Try it - block all the standard stealth scans, etc using something like the following...
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