Phishing prevention is not a “fire and forget” task. You have to make sure you have great data, double-check the information, and update the data to avoid “false positives.” And you have to do it all the time.

Different folks (see two below) have wondered publicly where our phishing data comes from and how OpenDNS uses the data. This post helps answer those questions, and more.

Phishing protection is a significant benefit to customers but it’s also a notable responsibility — under no circumstances does OpenDNS want to disrupt its customers’ normal Internet usage.

Note: if you just want speedy, reliable DNS without any protection from phishing, it’s available. (Not recommended, but available.) Use the OpenDNS preferences.

With that background out of the way, let me share what we added to our Frequently Asked Questions earlier this week.

How does OpenDNS decide if a site is a phishing site?

Currently, OpenDNS uses two methods for determining if a site is a phishing site:

1. Analysis of our network data, based on years of experience with DNS traffic.
2. Feeds from several network operators and others working against “Internet Bad Guys.”

There are three providers that we may identify and thank publicly for their participation:

1. Support Intelligence
2. Team Cymru
3. CastleCops PIRT

How do I report a phishing site to OpenDNS?

The fight against phishing isn’t just for the banks and big companies to tackle; you can help. Right now [July, 2006], we encourage submission of possible phishing sites via our contact form. Nothing will be blocked unless it’s verified.

How do I tell OpenDNS about a mistakenly-blocked site?

Every time OpenDNS shows the phish-blocked page (example), we offer the option to tell us to review the site. These requests are treated with urgency; we understand that false positives are painful, too.

Sites which are removed from the phishing list will be available to OpenDNS customers within one hour after review, and hopefully much sooner.

An extra detail: for the data from outside partners, we update our lists every six hours, including removing sites which no longer appear in the feeds.

PhishTank

PhishTank is a site OpenDNS will launch later this summer as a collaborative clearing house for data and information about phishing and malware on the Internet. PhishTank will be a free community site for validating and sharing this kind of data. There will be various statistics and an API, so anyone else who needs solid data to help fight Internet Bad Guys can use PhishTank as a source.

The point? The fight against phishing isn’t just for the banks and big companies to tackle; you can help. Several of you have sent us phishing URLs to add to our lists already — thank you! OpenDNS is selfishly interested in having the best, most up-to-date data available, but we don’t believe that proprietary data in this area is the answer: the API will be open to others, whether they contribute or not.

Too often now, phish reports go into a black hole where no response comes back and none of the aggregated intelligence is shared. PhishTank will be a solution to that problem.

Next steps

Yesterday, we were offered another validated feed of sites to avoid. Thanks! This looks to be a great additional resource, and once it’s confirmed and integrated, we’ll announce it here (with permission).

If you have data that will help us block the “Internet Bad Guys” from OpenDNS customers, please let me know. Use the contact form, or try me via direct email (first name at opendns.com).

p.s. As noted above, here are two blogs which took a look at OpenDNS right as we launched and wondered aloud about our phishing protection.

Another thing OpenDNS should work on ASAP is transparency. I’d really like to know the false positive rate on phishing sites. How many legitimate sites get flagged as a phishing site? (Tyler Longren, July 10, 2006)

Tyler, too early to have that specific stat, yet, but we hear you.

It looks like they are using blacklists to stop you from hitting known phishing sites. They don’t say where the list comes from or how ofter it is updated. (Mike Frank, July 11, 2006)

Mike, thanks for pushing us.

One week ago, OpenDNS opened up its free DNS service for everyone to use. It’s been a fun week, with lots of feedback. It’s great to be listening to customers, rather than predicting (guessing) what the reaction will be.

We’re reading everything and responding where possible. Probably still a few dozen of you who deserve an email response… it will come! Most of our public responses have been on individual blogs, to make sure the individual sees the response. David, our CEO, has been an active member of the NANOG and dns-operators mailing lists for years, and he’s contributed in those forums, too. We’ve heard from you over the phone, via email, via blog comment, in person and over IM (our team addresses are listed).

I’ve been flagging blog and media mentions on del.icio.us, and you can see the most recent 20 items listed in the OpenDNS press center. Or you can watch the del.icio.us page directly, if you prefer. Not every reference is positive. Fine… we learn a lot from listening to our critics. If we’ve missed a worthy reference, please bring it to my attention, either via email or even via a for:pencoyd tag in del.icio.us.

So far, we’ve been adding to our FAQ to address concerns and questions which we’ve seen come up in multiple places, whether blogs, articles, email or IM. If you haven’t read the FAQ in a while, take a look. It doesn’t shrink!

It might be more helpful for us to start responding on this blog, too. In the next few days, we’ll provide more details here about our identification of phishing sites, how we’re handling DNSBL and mail servers (hint: click on the new preferences link, top right of every page), our network buildout, additional stats and more.

Note: one of our favorites, a thorough review, with actual testing of the speed for that individual.

Tom Merritt and Veronica Belmont from CNET Buzz Out Loud took a few minutes on Monday to talk about OpenDNS.

Listen to the brief clip about OpenDNS (3 minutes, 10 seconds long; 1.5MB).

Thank you to Tom and CNET for permission to host the clip, which was pulled from the Buzz Out Loud show for July 10, 2006. They make tech pretty fun every day.

In the clip, Tom does a good job succinctly explaining what DNS is before talking about the service more broadly, rightly saying that it’s a pretty easy switch to make. Tom tried it personally, and both of them liked the idea (listen for yourself).

Tom and Veronica also discuss how OpenDNS interacts with corporate networks, and that’s something we should explain more.

Internal resources — for example, a web tool you might use for reporting vacation days — often takes advantage of local DNS resolution. In that case, using OpenDNS may prevent you from getting to those resources and you will have to turn off OpenDNS while you use them. There is no logical way for us to address internal resources, yet. On a related note, if on a VPN to a corporate network not using OpenDNS, you will be using the corporate DNS server, rather than OpenDNS, until you leave the VPN.

Of course, we encourage network admins to use OpenDNS as a forwarder, where internal requests are handled internally, and external requests are handled by OpenDNS. Happy to provide more details and help to anyone interested.

“Site-Lookup Service Foils Fraud” is Ryan Singel’s Wired News writeup about OpenDNS. Ryan and Kevin Poulsen, senior editor at Wired, publish 27BStroke6, a blog about security and privacy, so they grokked what we’re doing — putting some new intelligence into DNS.

Ulevitch’s seven-person startup is an attempt to revolutionize a layer of the internet’s architecture in order to clean its underbelly of scammers and spammers.

One important feature which is not yet available, but will be soon, is self-service control over the DNS settings. Ryan’s article, understandably, doesn’t mention this capability, since it’s not yet live.

The point? We’re going to put more control in your hands, so if you want to turn off features like typo correction or phishing prevention, you’ll be able to. Account management is the top priority now, to help demonstrate the power of control over your DNS. We think transparency and control will show you (not just tell) that we’re making the right choices. (UPDATE: July 17, 2006: try the preferences out. First step, with more to come. November 7, 2006: Set up an OpenDNS account.)

I encourage you to read the article for yourself. Having worked to explain what we do via our website, it’s rewarding to read an external description of OpenDNS that makes a lot of sense. Lots of people are reading the article and submitting excellent questions: we’ll be adding to the FAQ today.

I’m inspired by Simon Phipp’s post “Freedom to Leave” [via Tim Bray]. Simon’s talking about the openness of technology formats and standards, and reminds us all:

The fastest way to send early adopters packing is to make your cool new toy a roach motel.

Though we’re not about data formats, OpenDNS is against lock-in, too. We are asking you to choose OpenDNS, for various benefits. We’re confident that you’ll be happy with our DNS service. If you don’t agree, you’ll make another choice…and there’s nothing we could or would do to stop you.

DNS is easy to change (see for yourself), it’s under your control, and you have a choice.

P.S. I’ve felt this way before, though Simon (and others, like John Hagel) are more convincing.