Email security systems are missing 25 percent more emails containing dangerous file types, according to the latest quarterly Email Security Risk Assessment (ESRA) by email and data security product company Mimecast, compared with the quarter before. The ESRA is an aggregated report of tests that measure the efficacy of widely used email security systems.
Typically dangerous file types are rarely sent via email for legitimate purposes, such as: .jsp, .exe, .dll and .src, and can be used to further an attack. Every quarter Mimecast aggregates the results of ESRA tests and reports its findings. To date Mimecast has inspected more than 180 million emails that were deemed “safe” from these incumbent systems. Within these emails, the tests found 16,581 emails that contained dangerous file types.
The report also found 21,183,014 spam emails, 17,403 malware attachments, 42,350 impersonation attacks and 205,363 malicious URLS, all missed by these incumbent providers and delivered to users’ inboxes. This latest report concludes that an aggregate 12 per cent of all secured and filtered email were unwanted emails and thus were false negatives.
Lindsay Jack, security service director at Mimecast says: “Mimecast has seen an increase in security efficacy versus legacy vendors along with detailed information on the proliferation of threats of all types. The ESRA provides deep insights for our customers on the types of attacks threatening their business. Attacks we are seeing include key executives being targeted with cloud storage services exploits, impersonation attacks targeting legal, finance and administrative assistance as well as social engineering attacks against the C-suite. Mimecast helps organisations understand how they compare with other organisations in their geography or industry vertical. Additionally, these reports provide insights on the rise of new types of malware and key trends in malicious email campaigns.”
And Matthew Gardiner, cybersecurity strategist at Mimecast says: “Cybercriminals are constantly adapting their email-based attacks, looking for new ways to bypass security solutions that rely too heavily on reputation-based detection or file signature matches. This quarter we saw a particularly large jump in emails containing dangerous file types. Mimecast uses multiple layers and types of detection engines, combined with high performance analytics, a diverse set of threat intelligence sources, and computer aided human analysis to identify and stop unsafe emails from getting into our customers’ inboxes.”
Comment
Jake Moore at cyber security company ESET, said: “Emails are by far the largest attack vector for spreading malware or malware related services. With an estimated 281 billion emails being sent and received each day in 2018, it stands to reason that it is used as a very productive means to trick end users into downloading files, visiting dodgy websites or sending their logon credentials. Education and perseverance is one of the best ways to slow this practice down. Whilst email is a fantastic business and consumer aid, it is one practice that needs to be constantly checked and monitored.”
