A U.S senator is urging the Department of Homeland Security and other federal agencies to adopt DMARC to prevent impersonation attacks via email. Over the past few months, several government agencies have been targeted by phishers who have used government domains to send huge numbers of spam emails.
The emails appear legitimate as they have been sent from government-owned domains, and while the text in the emails often contains clues to suggest the emails are not genuine, the official domain adds sufficient authenticity to see many email recipients fooled.
The use of official domains by phishers is nothing new of course, but government-owned domains should be protected to prevent them being used in phishing campaigns. The problem is that in the vast majority of cases, insufficient controls have been implemented to prevent impersonation attacks.
Sen. Ron Wyden (D-Oregon) wrote to the Department of Homeland Security voicing his concerns about the problem, and specifically, the failure of federal agencies – including DHS – to use the Domain-based Message Authentication Reporting and Conformance (DMARC) standard.
DMARC is a proven tool that can help to prevent impersonation attacks via email by allowing email recipients to verify the sender of an email. If DMARC is used, it is possible to determine whether the emails have genuinely been sent from federal agencies or if they have been sent by a third party unauthorized to use the domain. In short, it will prevent impersonation attacks and protect consumers. If DMARC was used, it would make it much harder for government agencies to be impersonated.
The standard is recommended by the National Institute of Standards & Technology (NIST) as well as the Federal Trade Commission (FTC). DMARC has also recently been adopted in the UK by the British government with hugely positive results. Since DMARC has been implemented, the UK Tax agency alone has reduced impersonation attacks to the tune of 300 million messages in a single year.
The UK’s National Cyber Security Center (NCSC) has also created a central system where it processes all of the DMARC reports from all government agencies to monitor impersonation attacks across all government departments
Currently the Department of Homeland Security does not use DMARC and it is not used on the majority of government owned domains. The U.S. government owns approximately 1,300 domains, yet DMARC is only used on an estimated 2% of those domains.
Impersonation attacks are on the rise and numerous government agencies have been impersonated in recent months including the Department of Health and Human Services, the IRS and even the Defense Security Service – part of the U.S. Department of Defense.
Sen. Wyden suggests the Department of Homeland Security should immediately adopt DMARC and mandate its use across all federal agencies. DHS already scans other federal agencies for vulnerabilities under the Cyber Hygiene program. Sen. Wyden says DMARC scanning should be incorporated into that program. As in the UK, Sen. Wyden suggests a central repository should be created for all DMARC reports by the General Services Administration (GSA) to give DHA visibility into impersonation attacks across all federal agencies.