DNS

Yet Another Embarrassing IDN Gaff from ICANN

Hot on the heels of other ICANN Internationalized Domain Name (IDN) Top-Level Domain (TLD) launch errors, we now have another example of ICANN's failure to comprehend the differences between IDN and ASCII names, this time to the detriment of potential IDN registrants and the new IDN generic TLD (gTLD) Registries. This gaff really makes you wonder whether the SSAC and Multilinguism departments at ICANN have ever met. more

Technical Viability of Dotless Domain Names

It was never obvious at the outset of this grand Internet experiment that the one aspect of the network's infrastructure that would truly prove to be the most fascinating, intriguing, painful, lucrative and just plain confusing, would be the Internet's Domain Name System. After all, it all seemed so simple to start with: network applications rendezvous with their counterparts using protocol-level addresses, but we users prefer to use "natural" identifiers that act as aliases for these addresses. more

DNS Tunneling: Is It a Security Threat?

DNS tunneling -- the ability to encode the data of other programs or protocols in DNS queries and responses -- has been a concern since the late 1990s. If you don't follow DNS closely, however, DNS tunneling likely isn't an issue you would be familiar with. Originally, DNS tunneling was designed simply to bypass the captive portals of Wi-Fi providers, but as with many things on the Web it can be used for nefarious purposes. For many organizations, tunneling isn't even a known suspect and therefore a significant security risk. more

Is the Risk Real With the New gTLD Program? (An Interview with Verisign)

It's late in the new gTLD day and the program looks to be inching ever closer to the finish line. Yet last minute hiccups seem to be a recurring theme for this ambitious project to expand the Internet namespace far beyond the 300 odd active TLDs in existence today (counting generics and country codes). A drive for growth which is already underway, with 63 gTLD contracts now signed as of mid September... But will those users find themselves at greater risk because of this namespace expansion? That's what several parties have been asking in recent months. more

DNS Amplification Attacks: Out of Sight, Out of Mind? (Part 3)

Previous posts (Part 1 and Part 2) offer background on DNS amplification attacks being observed around the world. These attacks continue to evolve. Early attacks focused on authoritative servers using "ANY" queries for domains that were well known to offer good amplification. Response Rate Limiting (RRL) was developed to respond to these early attacks. RRL, as the name suggests, is deployed on authoritative servers to rate limit responses to target names. more

On the Time Value of Security Features in DNS

There are some real problems in DNS, related to the general absence of Source Address Validation (SAV) on many networks connected to the Internet. The core of the Internet is aware of destinations but blind to sources. If an attacker on ISP A wants to forge the source IP address of someone at University B when transmitting a packet toward Company C, that packet is likely be delivered complete and intact, including its forged IP source address. Many otherwise sensible people spend a lot of time and airline miles trying to improve this situation... The problems created for the Domain Name System (DNS) by the general lack of SAV are simply hellish. more

New gTLDs: The Registry Lock

Last week, The New York Times website domain was hacked by "the Syrian Electronic Army". Other famous websites faced the same attack in 2012 by the Hacker group "UGNazi" and, in 2011 by Turkish hackers. Basically, it seems that no Registrar on the Internet is safe from attack, but the launching of new gTLDs can offer new ways to mitigate these attacks. more

DNS Amplification Attacks: Out of Sight, Out of Mind? (Part 2)

This post follows an earlier post about DNS amplification attacks being observed around the world. DNS Amplification Attacks are occurring regularly and even though they aren't generating headlines targets have to deal with floods of traffic and ISP infrastructure is needlessly stressed -- load balancers fail, network links get saturated, and servers get overloaded. And far more intense attacks can be launched at any time. more

New gTLD Queries at the Root & Heisenberg’s Uncertainty Principle

Since Verisign published its second SSR report a few weeks back, recently updated with revision 1.1, we've been taking a deeper look at queries to the root servers that elicit "Name Error," or NXDomain responses and figured we'd share some preliminary results. Not surprisingly, promptly after publication of the Interisle Consulting Group's Name Collision in the DNS [PDF] report, a small number of the many who are impacted are aiming to discredit the report. more

DNS Amplification Attacks: Out of Sight, Out of Mind? (Part 1)

Geoff Huston's recent post about the rise of DNS amplification attacks offers excellent perspective on the issue. Major incidents like the Spamhaus attack Geoff mentions at the beginning of his post make headlines, but even small attacks create noticeable floods of traffic. These attacks are easy to launch and effective even with relatively modest resources and we see evidence they're occurring regularly. Although DNS servers are not usually the target of these attacks the increase in traffic and larger response sizes typically stress DNS infrastructure and require attention from operation teams. more