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Practical Steps for Protecting Domain Names

Patrick Jones, on behalf of the ICANN Security team

In the wake of high-profile hacking attacks against the New York Times, Twitter, Huffington Post, and others, we thought it would be useful to re-post the blog from November 2012 written by Dave Piscitello, ICANN’s Senior Security Technologist on What You Should Learn from the Diigo Domain Hacking incident. The post describes a set of practical steps that anyone who has a domain name registration can take to protect against domain hacking and related attacks.

Be aware that social engineering attacks may occur. Educate those who are responsible for maintaining domain name registrations and your web presence on the potential for attacks. Establish procedures for registering and maintaining domain names (and ensure that those procedures are followed). Use two-factor authentication. Ask your registrar about registrar locks, and use registry locks if offered by your registry operator.

These measures do not cover everything one can do to protect against attacks. We do suggest using the lessons from recent events to look at your existing practices and ask about additional measures one can take.

What You Should Learn From the Diigo Domain Hacking Incident



    Domain Name System
    Internationalized Domain Name ,IDN,"IDNs are domain names that include characters used in the local representation of languages that are not written with the twenty-six letters of the basic Latin alphabet ""a-z"". An IDN can contain Latin letters with diacritical marks, as required by many European languages, or may consist of characters from non-Latin scripts such as Arabic or Chinese. Many languages also use other types of digits than the European ""0-9"". The basic Latin alphabet together with the European-Arabic digits are, for the purpose of domain names, termed ""ASCII characters"" (ASCII = American Standard Code for Information Interchange). These are also included in the broader range of ""Unicode characters"" that provides the basis for IDNs. The ""hostname rule"" requires that all domain names of the type under consideration here are stored in the DNS using only the ASCII characters listed above, with the one further addition of the hyphen ""-"". The Unicode form of an IDN therefore requires special encoding before it is entered into the DNS. The following terminology is used when distinguishing between these forms: A domain name consists of a series of ""labels"" (separated by ""dots""). The ASCII form of an IDN label is termed an ""A-label"". All operations defined in the DNS protocol use A-labels exclusively. The Unicode form, which a user expects to be displayed, is termed a ""U-label"". The difference may be illustrated with the Hindi word for ""test"" — परीका — appearing here as a U-label would (in the Devanagari script). A special form of ""ASCII compatible encoding"" (abbreviated ACE) is applied to this to produce the corresponding A-label: xn--11b5bs1di. A domain name that only includes ASCII letters, digits, and hyphens is termed an ""LDH label"". Although the definitions of A-labels and LDH-labels overlap, a name consisting exclusively of LDH labels, such as"""" is not an IDN."