A quarterly threat report revealed malicious email payloads increased in both volume and frequency between the first and second quarters of 2018.

Researchers from Proofpoint detected a 36 percent increase in malicious messages between the first and second quarters of this year, according to the August 2018 report. While this fell short of the peak volumes the enterprise security firm observed in 2016 and 2017, the report noted that this past quarter stood out for the variety of threats the researchers discovered in phishing campaigns.

Ransomware, for example, accounted for 11 percent of malicious email payloads, according to the report. While ransomware was not the dominant payload in the second quarter, bad actors are using it as part of their everyday toolkits, and attacks appear to be consolidating around major strains like GandCrab and Sigma.

Malicious Emails Carry Multiple Payloads in Q2

This trend suggests that attackers are becoming increasingly creative with their malicious payloads. In some cases, they’re sending out malware that can behave like multiple digital threats. Researchers at ThreatFabric observed this cross-functionality in June 2018 with MysteryBot, an Android banking Trojan capable of delivering a keylogger and ransomware.

Some threat actors are also launching attack domains containing multiple payloads. For example, Fortinet observed a single mass spam campaign pushing three separate samples of GandCrab version 2.1 earlier in 2018.

As a result, businesses of all sizes face a challenge to protect themselves against a wide variety of digital threats as opposed to just a few payload categories, which can consume significant time and resources.

How Can Organizations Improve Email Security?

Security experts recommend employing a layered approach to email security, which should include spam control, email scanning, security information and event management (SIEM), and other antispam controls. Security professionals should also consider using a threat intelligence platform that integrates with their email inbox to quickly share and collect threat data.

Sources: Proofpoint, ThreatFabric, Fortinet