DNS Security

Information Protection for the Domain Name System: Encryption and Minimization

In previous posts in this series, I've discussed a number of applications of cryptography to the DNS, many of them related to the Domain Name System Security Extensions (DNSSEC). In this final blog post, I'll turn attention to another application that may appear at first to be the most natural, though as it turns out, may not always be the most necessary: DNS encryption. (I've also written about DNS encryption as well as minimization in a separate post on DNS information protection.)

Securing the DNS in a Post-Quantum World: Hash-Based Signatures and Synthesized Zone Signing Keys

In my last article, I described efforts underway to standardize new cryptographic algorithms that are designed to be less vulnerable to potential future advances in quantum computing. I also reviewed operational challenges to be considered when adding new algorithms to the DNS Security Extensions (DNSSEC). In this post, I'll look at hash-based signatures, a family of post-quantum algorithms that could be a good match for DNSSEC from the perspective of infrastructure stability.

Securing the DNS in a Post-Quantum World: New DNSSEC Algorithms on the Horizon

One of the "key" questions cryptographers have been asking for the past decade or more is what to do about the potential future development of a large-scale quantum computer. If theory holds, a quantum computer could break established public-key algorithms including RSA and elliptic curve cryptography (ECC), building on Peter Shor's groundbreaking result from 1994.

Newer Cryptographic Advances for the Domain Name System: NSEC5 and Tokenized Queries

In my last post, I looked at what happens when a DNS query renders a "negative" response -- i.e., when a domain name doesn't exist. I then examined two cryptographic approaches to handling negative responses: NSEC and NSEC3. In this post, I will examine a third approach, NSEC5, and a related concept that protects client information, tokenized queries. The concepts I discuss below are topics we've studied in our long-term research program as we evaluate new technologies.

Cryptographic Tools for Non-Existence in the Domain Name System: NSEC and NSEC3

In my previous post, I described the first broad scale deployment of cryptography in the DNS, known as the Domain Name System Security Extensions (DNSSEC). I described how a name server can enable a requester to validate the correctness of a "positive" response to a query -- when a queried domain name exists -- by adding a digital signature to the DNS response returned.

The Domain Name System: A Cryptographer’s Perspective

As one of the earliest protocols in the internet, the DNS emerged in an era in which today's global network was still an experiment. Security was not a primary consideration then, and the design of the DNS, like other parts of the internet of the day, did not have cryptography built in. Today, cryptography is part of almost every protocol, including the DNS. And from a cryptographer's perspective, as I described in my talk at last year's International Cryptographic Module Conference (ICMC20), there's so much more to the story than just encryption.

DNS Oblivion

Technical development often comes in short, intense bursts, where a relatively stable technology becomes the subject of intense revision and evolution. The DNS is a classic example here. For many years this name resolution protocol just quietly toiled away. The protocol wasn't all that secure, and it wasn't totally reliable, but it worked well enough for the purposes we put it to.

97% of All Global 2000 Companies at Risk from SAD DNS Attack

There is a new threat in town known as "SAD DNS" that allows attackers to redirect traffic, putting companies at risk of phishing, data breach, reputation damage, and revenue loss. What is SAD DNS? No, it isn't the domain name system (DNS) feeling moody, but an acronym for a new-found threat -- "Side-channel AttackeD DNS" discovered by researchers that could revive DNS cache poisoning attacks.

Holiday Shoppers Beware: Tips on Protecting Brand Owners and Consumers from Domain Security Threats

With the COVID-19 pandemic persisting, online shopping will be the preferred method for the 2020 holiday shopping season. While staying home to shop is the safest option right now, it means consumers are more vulnerable to online fraud, counterfeits, and cyber crime. Increased online activity provides opportunities for unscrupulous infringers to abuse trusted brand names to drive visitors to their own fraudulent content.

Authenticated Resolution and Adaptive Resolution: Security and Navigational Enhancements to the DNS

The Domain Name System (DNS) has become the fundamental building block for navigating from names to resources on the internet. DNS has been employed continuously ever since its introduction in 1983, by essentially every internet-connected application and device that wants to interact online. Emerging from an era where interconnection rather than information security was the primary motivation, DNS has gradually improved its security features.