DMARC doesn't fix Phishing

Not a new thing, but a nice example just popped up in my inbox on my phone.

 
But FedEx solved their entire phishing problem when they published a strict p=reject DMARC record, right?
This didn’t come from fedex.com. It came from another domain that looks vaguely like fedex.com – what that domain is doesn’t matter, as the domain it’s sent from isn’t displayed to the user on my phone mail client. Nor is it displayed to the user by Mail.app on my desktop, unless you turn off Mail → Preferences … → Viewing → Use Smart Addresses.

That lookalike domain could pass SPF, it could be used as d= in DKIM signing, it could even be set up with DMARC p=reject. And the mail is pixel identical to real mail from fedex.com.
On my desktop client I can hover over the link and notice it looks suspicious – but it’s no more suspicious looking than a typical ESP link-tracking URL. And on mobile I don’t even get to do that.
SPF and DKIM and DMARC can temporarily inconvenience phishers to the extent that they have to change the domain they’re sending from, but it’ll have no effect on the vulnerability of most of your audience to being phished using your brand.

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Happy New Year!

Well, we mostly survived 2016. A year ago I was making predictions about how 2016 would be the year of email security. I was thinking of things like TLS and authentication and access to the inbox. It wasn’t out of the question, Gmail said they’d be turning on p=reject sometime mid-year. They also were suggesting that they would be putting more value on messages that aligned, even in the absence of a DMARC signature. The first still hasn’t happened, and the second doesn’t appear to be in place, either.
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That doesn’t mean email security wasn’t a hot topic in 2016. In fact, the use of a private email server was a major topic during the US elections. We also had spear-phishing play a major role in the compromise of campaign systems. I didn’t talk much about that here when it happened, but news reports make it clear that Chairman Podesta and others were targeted for compromise. The NY Times has a more in depth article with broader context around the attacks and how emails were used to infiltrate a major political party.
The irony is with all the time spent talking about how insecure the private server was, that server wasn’t compromised. Instead, the compromise was at Gmail.
We all need to pay attention to our email and how we use it. It also means when we’re sending bulk and marketing email we need to consider the private and personal information we’re putting in messages. Do you send PII? Is there a way you don’t have to? What can we do to protect our brand and our users?
It’s not just bulk email we need to think about, either. Personal email can contain PII, or personal information. A common saying among some of my security friends is “never put in email anything you wouldn’t want to see on the front page of the Washington Post or NY Times.” That’s an easy thing to say, but the convenience of email makes it easy to share information that we may not want on the front page of either paper. Many of us aren’t actually targets of malicious activity so we don’t have to worry about being targeted the way elected and other officials are. But that doesn’t mean we are not at risk. It just means we’re at less risk than others.
Email is a frequent vector for malicious actors to access computers. Most, if not all of the major breeches in the last few years have started with a phishing attack of some sort. The attacks are planned out and sophisticated. This is not going to get better. The phishers are smart and plan the attacks.  We also need to be more personally aware of security given the current political climate. We need to take steps to protect ourselves more than we have in the past.
Security is more important than ever and we all need to protect ourselves.

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Phishing increasingly sophisticated

Phishing is an online threat that’s been around for more than 20 years. I initially heard of it in relation to spammers taking over an AOL account to send out spam. These days phis is more dangerous and more sophisticated. Phishing is not just used to send spam. It’s used to take over elections; it’s used to steal millions of dollars. Experts estimate that globally phishing costs companies over 9 billion dollars a year.
Even in the last two weeks we’ve seen 2 major phishing incidents. One targeted Google Docs, one targeted Docusign. Reading the news reports these are different than many of the more common phishing attacks and, to me, represent an evolution in standard phishing techniques.

The Google attack in early May was an evolution in getting access to a Google account. Instead of directing users to a fake Gmail login page, the phish asked users to allow “Google Docs” (actually an app controlled by the phisher) to access to their Google account.
I’m sure all of you have used an app or website that lets you login with Facebook or Gmail or Twitter. This is all done with a protocol called OAuth. OAuth is also how you give access to mailbox management tools like I discussed a few weeks ago.  Basically, OAuth lets users grant access and permission to a site or application using a second site without revealing their username and password. (It’s more complicated than I want to discuss, but if you’re looking for some information check out some of the sites I’ve found: wikipedia, Varonis blog, Digital Ocean knowledge base, or just search google for oauth.)
The switch from asking for a password to asking for access is, to my mind, a significant change. Now we have to be aware of what we’re authorizing and make sure that app isn’t malicious.
The Docusign phish is another evolution.  As I was looking at the phish I received yesterday I realized that it was sent to a tagged address. A tagged address only Docusign had. None of my other, heavily phished, addresses received the phish. None of Steve’s addresses received the phish. This wasn’t a widespread spray and pray phishing attack. The phishers targeted Docusign users. Yesterday afternoon, Docusign confirmed that someone stole user addresses.
This is a switch from just randomly looking for victims to targeting users of a specific service.
Phishing attacks look for the weakest links to gain access to computers, information, and money. The weakest links are always humans. Phishers have adapted to security measures for the last 20 years. There is zero reason that they won’t continue to adapt.
 
 
 

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You're kidding me

All the authentication and DMARC in the world can’t save you from stupid.
I just got a survey request from my bank. Or, at least, it claimed to be from my bank.

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