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This post was co-authored by Sarah McKune, a senior researcher at the Citizen Lab. Public attention to the secretive world of cyber espionage has risen to a new level in the wake of the APT1: Exposing One of China's Cyber Espionage Units report by security company Mandiant. By specifically naming China as the culprit and linking cyber espionage efforts to the People's Liberation Army, Mandiant has taken steps that few policymakers have been willing to take publicly, given the significant diplomatic implications.
As noted in the first part of this series, Security and Reliability encompasses holistic network assessments, vulnerability assessments, and penetration testing. In this post I'd like to go deeper into network assessments. I stated last time that the phrase "network assessment" is broad.
I co-authored a book in 2005, titled "Extreme Exploits: Advanced Defenses Against Hardcore Hacks." My chapters focused on securing routing protocols such as BGP, and securing systems related to DMZs, firewalls, and network connectivity. As I look back over those chapters, I realize that the basic fundamentals of network security really haven't changed much even though technology has advanced at an incredible pace. "Defense in depth" was a hot catch phrase seven years ago, and it still applies today.
In the first part of this trilogy, I discussed the importance of automatically provisioned second generation DNS in connection with Software Defined Networking (SDN) and Software Defined Data Centre (SDDC). In the second post, I talked about IP addressing, private enterprise networks, and how DHCP does not meet the requirements of multitenant Infrastructure-as-a-Service (IaaS) cloud environments. I will now wrap up this trilogy by putting these two thesis into real-life context.
In part 1, I talked about some of the risks associated with BYOD. But there are actions you can take to greatly reduce this risk. One effective method for limiting the risk of BYOD is to employ DNS-based security intelligence techniques. DNS-based security intelligence makes use of an enterprise's caching DNS server to monitor and block DNS queries to known botnet command and control (C&C) domains.
Ah, BYOD. How I love thee. BYOD, or "Bring Your Own Device", gives me choices. I can use a device at work I actually like and am most effective with. (How did I ever get by without my iPad?) But BYOD comes with challenges. Personal devices can be infected with malware. Once they're connected to an enterprise's network, they can be controlled by a bot master to hijack enterprise resources and wreak havoc as part of a botnet.
It is just another phishing case. Why should I care? I happened to receive my own copy of the phishing email message. Most Internet users will just smile bitterly before deleting it. I checked it to see why it had gone through the spam filters. It had no URL in the text but a reply-to address. So it needed a valid domain name, and had one: postfinances.com. PostFinance (without trailing "s") is the payment system of the Swiss Post. It has millions of users.
In general, a network firewall is just a traffic filter... Filtering rules can be anything from "allow my web server to hear and answer web requests but not other kinds of requests" to "let my users Ping the outside world but do not let outsiders Ping anything on my network." The Internet industry has used firewalls since the mid-1980's and there are now many kinds, from packet layer firewalls to web firewalls to e-mail firewalls. Recently the DNS industry has explored the firewall idea and the results have been quite compelling. In this article I'm going to demonstrate a DNS firewall built using RPZ (Response Policy Zones) and show its potential impact on e-mail "spam".
The capabilities IPv6 provides will enhance online security, but the shift to the new Internet address scheme may also present risks if not properly managed. Previously, Internet security was largely an after-thought for the early Internet, as its primary purpose was to facilitate open, end-to-end, any-to-any communications and information exchange for bridging and accelerating research efforts. Today, we have a much more complex online ecosystem that spans billions of users across the globe and serves not only as an engine for e-commerce, but as an engine for all commerce.
Throughout the second half of 2012 many security folks have been asking "how much is a zero-day vulnerability worth?" and it's often been hard to believe the numbers that have been (and continue to be) thrown around. For the sake of clarity though, I do believe that it's the wrong question... the correct question should be "how much do people pay for working exploits against zero-day vulnerabilities?"