Defending Against COVID Email Spoofing Attacks with DMARC

Malicious email is multiplying exponentially due to the COVID-19 crisis - and cyber criminals show no signs of slowing down. In April of 2020, Guardian Digital has identified more phishing emails than in any month prior since the company’s inception in 1999. This alarming trend is consistent with a recent report published by Google, which indicates that from April 9-16, 2020, the tech giant saw 18 million COVID-related phishing and malware attacks daily.

In this new digital environment where attacks are on the rise, it is more important than ever that organizations protect remote workers from email spoofing and phishing scams.

Safeguard Your Inbox from Sender Fraud with DMARC Enforcement: What You Need to Know

DMARC enforcement is critical in preventing the serious consequences of identity deception, adding an identity check to all inbound email messages. This sender authentication protocol is designed to give email security providers and email domain owners the ability to protect their domain from email spoofing and sender fraud - mitigating the risk of phishing attacks, business email compromise (BEC) and other dangerous email scams. Once a DMARC Domain Name System (DNS) entry is created, a receiving email server can authenticate incoming email based on the instructions specified by the domain owner within the DNS entry. If the email passes the authentication, it is deemed legitimate and will be delivered. If the email fails the authentication, it is flagged as fraudulent and is either quarantined or rejected. 

When it comes to fortifying your email with DMARC enforcement, there are some important points to consider. Be aware that not all email security providers implement this powerful sender authentication protocol to its fullest. Moreover, defense-in-depth is essential to any effective security strategy, and DMARC is far more effective when it serves as a component of a multi-layered email security approach. Guardian Digital security researchers have identified a list of high-priority, frequently spoofed domains that Guardian Digital EnGarde Cloud Email Security is validating with DMARC enforcement to protect all clients from spoofing, phishing and malware exploits. These domains include:

• @who.org (World Health Organization)
• @cdc.gov (Center for Disease Control and Prevention)
• @hhs.gov (Department of Health and Human Services)
• @irs.gov (Internal Revenue Service)
• @treasury.gov (US Dept. of the Treasury)

Using DMARC, we’re able to definitively tell whether it was actually the WHO or the CDC who sent a specific email to one of our clients. With this information, we can then reject mail attempting to spoof these domains and only allow legitimate email to get through to our clients' inboxes. By implementing DMARC authentication for our clients, others on the Internet can check their DMARC signature to ensure that emails they receive from our clients are properly signed, preventing our clients’ domains from being spoofed. Here is how to use the “dig” command to display the DMARC record for a domain using guardiandigital.com as an example:

# dig +short txt _dmarc.guardiandigital.com

"v=DMARC1; p=none; pct=100; rua=This email address is being protected from spambots. You need JavaScript enabled to view it.This email address is being protected from spambots. You need JavaScript enabled to view it.; ruf=This email address is being protected from spambots. You need JavaScript enabled to view it.This email address is being protected from spambots. You need JavaScript enabled to view it.; fo=1; adkim=r; aspf=r; rf=afrf; ri=86400; sp=none"

The heightened email threat environment brought about by COVID-19 reinforces the importance of sender authentication through DMARC enforcement, implemented as part of a comprehensive, multi-layered cloud email security solution. Guardian Digital CEO Dave Wreski warns, “Just as you prioritize frequent hand washing, wearing a mask in public and keeping a six-foot distance from others, it is crucial that businesses and users prioritize digital security in this dangerous, uncertain time. Now is definitely not the time to overlook the importance of effective email security.”

We have assembled a list of tips and best practices for staying safe online while working remotely during COVID-19 that we recommend you share with your friends and co-workers.

Are you interested in defending against phishing, spoofing and other malicious threats with a threat-ready, fully-managed cloud email security solution? We want to help you successfully navigate this difficult time, and are currently offering a free security assessment. Partner with a leader in the industry today - email This email address is being protected from spambots. You need JavaScript enabled to view it.