Monthly Archives: January 2018

Improving MX

In recent months, DMARC has become increasingly mentioned in the news as a way to reduce spam, improve email deliverability and reduce the potential for fraud and phishing.

  • In early 2017, UK National Health Service required DMARC as the default for email services.
  • In July, a US Senator Ron Wyden sent an open letter to the US Department of Homeland Security requesting the agency take steps to protect all Federal agencies with DMARC.
  • In August, the UK’s HMRevenues & Customs announced that it had stopped over 300k phishing emails using DMARC.
  • In October, the US Department of Homeland Security directed Federal agencies to adopt security technologies like DMARC.

With all this attention, businesses are starting to realize that adopting DMARC helps them in two ways:

  • Inbound – using DMARC to screen incoming emails for compliance can limit your company’s exposure to fraud and phishing emails, scams and malware.
  • Outbound – sending email that is DMARC compliant can improve email delivery to your customers and limit the potential negative impacts of 3rd parties that try to use your domain for fraud or phishing.

How does DMARC work for outbound email?

DMARC works in conjunction with two other technologies: SPF and DKIM.  SPF allows you to designate 3rd parties as legitimate senders for your domain.  More on SPF here. DKIM allows you to take responsibility for your email by cryptographically signing your email.  SPF, DKIM and DMARC use DNS records to specify the IP addresses, domains and security keys for your particular configuration.

DMARC requires both SPF and DKIM to function properly.  Once you setup SPF and DKIM you can setup DMARC to get information on how your outbound emails are performing – whether or not emails coming “from” your domain are compliant with the definitions in your SPF and how many of your emails are compliant with DKIM.

With a DMARC record, you specify an email address for aggregate feedback about your SPF and DKIM compliance, an email address for specific forensic feedback related to failed emails and how email that fails compliance should be handled by the recipient – ignored, quarantined or rejected.

How do you improve your DMARC Compliance?

DMARC Compliance is based upon SPF and DKIM compliance rates.  In order to improve your outbound DMARC compliance and therefore your email delivery rates, you must:

Setup DMARC with both RUA and RUF

RUA and RUF designate email addresses where you can receive summaries of authentication and alignment pass/fail and detailed forensic information on failed emails.  As this is the only way to receive feedback, setting up these email addresses is extremely important.

Monitoring your DMARC Feedback

Inbox providers will respond to these RUA and RUF tags by sending summaries.  Unfortunately, the summary digests and forensic details are not quite human readable.  If your outbound email volume is over a few hundred emails a day, you need to consider some way to decode these digests.

Act on DMARC Forensic Responses

DMARC forensic reports provide you with detailed information about the emails that have failed SPF, DKIM and DMARC checks.  You can use this information to investigate threats to your brand or problems with your 3rd party emailers.

Summary

The best way to improve email delivery is to adopt new technologies SPF, DKIM and DMARC. With the right tool, you can keep tabs on your email configuration, understand the threat to your brand, and improve email delivery.

Adopting DKIM can make a huge difference in how the email you send is perceived by recipients.  With DKIM you are taking ownership of an email by cryptographically signing each email.  Recipients then decode the signature to verify that you sent the email.  DKIM, in short, is like putting a wax seal on a letter that uniquely identifies you.

How can you improve DKIM compliance?

Get Informed

The first thing you need to improve DKIM compliance is a method to understand what your current compliance rate is.  To do this, you need:

  1. Adopt DMARC.
  2. Have a method to parse and report on DMARC digests coming from inbox providers.

DMARC responses from inbox providers are often not-quite human readable and the larger the volume of email you send, the more complex the responses.  To parse these, you need a product that summarizes them and provides reports that you can understand.

Get Control

Now that you have insight into what emailers are compliant, the second step to improving your DKIM compliance is to take control of the compliance of your internal emails and 3rd party emailers.

Investigate internal systems that might be sending email on your behalf and make sure that those systems are capable of signing outbound email with your DKIM signature.  These could be anything from marketing automation and sales systems to order entry, vendor management or customer support.  Regardless if they are home-grown or off-the-shelf, if the system is sending email, it needs to be DKIM compliant or the email may be rejected.

Similarly to internal systems, you must take a look at external, 3rd party providers to understand if they can be DKIM compliant.  Most external providers can sign email with a DKIM key, however, email forwarders are much less likely to be DKIM compliant than bulk emailers or other 3rd party service providers.  Talk with each of them to setup DKIM compliant email.

Repeat

Getting DKIM compliant is not a one-time project, but an on-going process.  To ensure high levels of compliance long-term, you will need to:

  • Regularly check compliance rates
  • On-board new internal and 3rd party systems to be compliant
  • Setup processes to assess new applications and providers based on their DKIM support

Summary

DKIM Compliance is an on-going process that requires regularly investigation of DKIM compliance rates with tools that give you insight into the IP addresses and 3rd party tools and domains that are sending email on your behalf.

What is Email Phishing?

There has been a lot of discussion about Email Fraud and Phishing lately.  Email is still the largest threat vector for hacking and information theft.  Email phishing is one of the best way to obtain access to accounts, but what is email phishing really?

Phishing is when a 3rd party, typically a hacker or xxalicious website, uses the brand identity of a company to lull a user into exposing private information.  Phishing emails target email address with an email that looks just like a legitimate service provider to implant malware in a download or obtain login credentials for that domain.  For example, you might receive an email that looks like it comes from a financial institution like Paypal (see mine below) asking you to download a document or go to a link to stop or start a transaction, or change your password.

phishingemail

Example Phishing Email

Identifying Phishing Emails

Phishing groups and hackers are constantly changing their patterns to improve both their targeting and the effectiveness of their emails in order to exploit users, but there are a few characteristics in common for every phishing email.

Phishing emails leverage a strong brand

In my example, the “From” email address used Paypal’s, but I have seen it with many big brands, especially in credit cards, financial, banking and insurance industries.  Ask yourself:  Do you really have an account? Is this the email address for that account? Have you done anything with the account lately?

There is a sense of urgency

The email will require you to “act soon” or it will cost you money.  This sense of urgency makes you react before you think.  Take a breath before acting on any email that looks really important.  

Quality Varies

Some phishing emails, like the one above, look good on the surface.  For example, the logos look correct, the fonts and color scheme are appropriate and some of the language is even straight from legitimate emails.  However, when you read deeper you can see spelling mistakes, grammatical errors or other areas where it is clear the writer was not a native English speaker.  Notice above that “DeLL” is not written correctly nor is the phrase “This not you?” proper English.  Take a moment to read the information presented in the email and check grammar and spelling.

“From” domain and Return Path Domain will not match

It is relatively easy to spoof a “From” address.  Email Standards allow 3rd party emailers to send email on behalf of another domain, otherwise inbox providers like Google and Outlook.com or bulk email providers could not send email for the business or personal domains they host.  If “From” and Return Path do not match and the Return Path looks random or shady, it’s a good chance you have a phishing email.  Further, most companies will not use a 3rd party to send important account information emails like the one above, but their own internal servers.  Check the Return Path email address in the header to see if it looks legitimate.

There is an attachment

If you are required to download anything that you did not ask the company for, then it is probably a phishing email and may contain malware.  Even PDFs or DOCs can contain malware payloads.  At minimum, they are trying to lull you into thinking that their fake document is valid so that they can get personal, private or financial data from you.  Do not download attachments you did not ask for.

Links on the page go to a different domain

Often a phishing email will include a link to a 3rd or 4th domain or just to an IP address.  The goal here is to get you to click unsuspectedly on any link so they can further the con and grab your information when you attempt to login to their fake website.  Sometimes the domains even look like subdomains or related domains.  Always check links before clicking on them.  If in doubt of any link, open a clean window and navigate to the company’s website and login to your account from there to check on the issue.  

Two major flaws in computer chips could leave a huge number of computers and smartphones vulnerable to security concerns, researchers revealed Wednesday.

And a U.S. government-backed body warned that the chips themselves need to be replaced to completely fix the problems.

The flaws could allow an attacker to read sensitive data stored in the memory, like passwords, or look at what tabs someone has open on their computer, researchers found. Daniel Gruss, a researcher from Graz University of Technology who helped identify the flaw, said it may be difficult to execute an attack, but billions of devices were impacted.

Related: Apple says all Macs and iOS devices affected by chip flaws

Called Meltdown and Spectre, the flaws exist in processors, a building block of computers that acts as the brain. Modern processors are designed to perform something called "speculative execution." That means they predict what tasks they will be asked to execute and rapidly access multiple areas of memory at the same time.

That data is supposed to be protected and isolated, but researchers discovered that in some cases, the information can be exposed while the processor queues it up.

Researchers say almost every computing system -- desktops, laptops, smartphones, and cloud servers -- is affected by the Spectre bug. Meltdown appears to be specific to Intel (INTC) chips.

"More specifically, all modern processors capable of keeping many instructions in flight are potentially vulnerable. In particular, we have verified Spectre on Intel, AMD, and ARM processors," the researchers said.

Related: What to do about the Spectre and Meltdown risks

Government agencies issued statements warning users about the vulnerabilities.

The U.S. Computer Emergency Readiness Team said that while the flaws "could allow an attacker to obtain access to sensitive information," it's not so far aware of anyone doing so.

The agency urged people to read a detailed statement on the vulnerabilities by the Software Engineering Institute, a U.S.-government funded body that researches cybersecurity problems.

The institute said that "fully removing the vulnerability requires replacing vulnerable [processor] hardware."

It later changed its guidance on Thursday to suggest updating software was enough. The institute didn't say why it had made the change and didn't immediately respond to a request for further information.

It said the problems affect technology giants including Apple, Google and Microsoft.