WatchGuard Technologies released its latest quarterly Internet Security Report, detailing the top malware trends and network security threats analyzed by WatchGuard Threat Lab researchers during Q2 2021.

The report also includes new insights based on endpoint threat intelligence detected throughout the first half of 2021. Top findings from the research uncovered an astonishing 91.5% of malware arriving over HTTPS-encrypted connections, alarming surges across fileless malware threats, dramatic growth in ransomware, a significant increase in network attacks, and much more.

Among its most notable findings, WatchGuard’s Q2 2021 Internet Security Report reveals:

Massive amounts of malware arrive over encrypted connections – In Q2, 91.5% of malware arrived over an encrypted connection, a dramatic increase over the previous quarter. Put simply, any organization that is not examining encrypted HTTPS traffic at the perimeter is missing 9/10 of all malware.

Jake Williams, Co-Founder and CTO at BreachQuest, an Augusta, Ga.-based provider of incident response, says, “It’s unsurprising that most malware is delivered over encrypted channels. This research puts numbers to what would otherwise be anecdotes. I would have guessed the number was north of 95%. Monitoring encrypted traffic is important both to detect the delivery of malware and to observe command and control (C2) patterns. TLS 1.3 and Perfect Forward Secrecy (PFS) make this more difficult, and threat actors know it. Organizations considering encrypted traffic monitoring solutions should examine how they will deal with PFS to ensure they gain full value from the investment.”

Malware is using PowerShell tools to bypass powerful protections – AMSI.Disable.A showed up in WatchGuard’s top malware section for the first time in Q1 and immediately shot up for this quarter, hitting the list at #2 overall by volume and snagging the #1 spot for overall encrypted threats. This malware family uses PowerShell tools to exploit various vulnerabilities in Windows. But what makes it especially interesting is its evasive technique. WatchGuard found that AMSI.Disable.A wields code capable of disabling the Antimalware Scan Interface (AMSI) in PowerShell, allowing it to bypass script-security checks with its malware payload undetected.

Fileless threats soar, becoming even more evasive – In just the first six months of 2021, malware detections originating from scripting engines like PowerShell have already reached 80% of last year’s total script-initiated attack volume, which itself represented a substantial increase over the year prior. At its current rate, 2021 fileless malware detections are on track to double in volume YoY.

Network attacks are booming despite the shift to primarily remote workforces – WatchGuard appliances detected a substantial increase in network attacks, which rose by 22% over the previous quarter and reached the highest volume since early 2018. Q1 saw nearly 4.1 million network attacks. In the quarter that followed, that number jumped by another million – charting an aggressive course that highlights the growing importance of maintaining perimeter security alongside user-focused protections.

Ransomware attacks back with a vengeance – While total ransomware detections on the endpoint were on a downward trajectory from 2018 through 2020, that trend broke in the first half of 2021, as the six-month total finished just shy of the full-year total for 2020. If daily ransomware detections remain flat through the rest of 2021, this year’s volume will reach an increase of over 150% compared to 2020.

Big game ransomware hits eclipse “shotgun blast”-style attacks – The Colonial Pipeline attack on May 7, 2021, made it abundantly and frighteningly clear that ransomware as a threat is here to stay. As the quarter’s top security incident, the breach underscores how cybercriminals are not only putting the most vital services – such as hospitals, industrial control, and infrastructure – in their crosshairs but appear to be ramping up attacks against these high-value targets as well. WatchGuard incident analysis examines the fallout, what the future looks like for critical infrastructure security, and steps organizations in any sector can take to help defend against these attacks and slow their propagation.

Old services continue to prove worthy targets – Deviating from the usual one to two new signatures seen in previous quarterly reports, there were four brand new signatures among WatchGuard’s top 10 network attacks for Q2. The most recent was a 2020 vulnerability in the popular web scripting language PHP, but the other three aren’t new. These include a 20ll Oracle GlassFish Server vulnerability, a 2013 SQL injection flaw in medical records application OpenEMR, and a 2017 remote code execution (RCE) vulnerability in Microsoft Edge. While dated, all still pose risks if left unpatched.

Microsoft Office-based threats persist in popularity – Q2 saw one new addition to the 10 most widespread network attacks list, and it made its debut at the very top. The signature, 1133630, is the 2017 RCE vulnerability mentioned above that affects Microsoft browsers. Though it may be an old exploit and patched in most systems (hopefully), those that have yet to patch are in for a rude awakening if an attacker can get to it before they do. In fact, a very similar high-severity RCE security flaw tracked as CVE-2021-40444 made headlines earlier this month when it was actively exploited in targeted attacks against Microsoft Office and Office 365 on Windows 10 computers. Office-based threats continue to be popular when it comes to malware, which is why we’re still spotting these tried-and-true attacks in the wild. Fortunately, they’re still being detected by tried-and-true IPS defenses.

Phishing domains masquerade as legitimate, widely recognized domains – WatchGuard has observed an increase in the use of malware recently targeting Microsoft Exchange servers and generic email users to download remote access trojans (RATs) in highly sensitive locations. This is most likely due to Q2 being the second consecutive quarter that remote workers and learners returned to either hybrid offices and academic environments or previously normal behaviors of on-site activity. Strong security awareness and monitoring of outgoing communications on devices that aren’t necessarily connected directly to the connected devices is advised in any event or location.

Taylor Gulley, Senior Application Security Consultant at nVisium, a Falls Church, Virginia-based application security provider, explains, “With the world moving toward secure communications, it makes sense that malware distributors will do so, too. Along with this fact, there is a rising desire for companies to inject themselves into that communication, particularly where it concerns network traffic to and from their employees in order to catch malicious traffic early. This requirement to monitor encrypted traffic for threats creates a dilemma where one must determine if the benefits outweigh the risks of such measures. While being a man-in-the-middle is a frequently sought position for an attacker, when a company attains the same position, similar risks present themselves. Though decrypting network traffic provides insight into the contents of the traffic, if HTTPS traffic is being decrypted and logged, then by the nature of that traffic, information that was supposed to be private between two parties on the internet is now available

on that system in plain text. This leads to passwords and session tokens being stored in log files.”

“For example, let’s say an employee is managing their health plan from a work computer. As a result, now privileged personal data such as medical information can be stored in log files. All of this increases the attack surface for an adversary to exploit, and pilfer adds,” adds Gulley. “Rather than work to undermine secure communications, it may be better to focus on proper endpoint security, as well as employee security awareness. By proceeding in this manner, your workforce is less likely to fall for the types of ploys that malware distributors use in the first place. Subsequently, if there is a lapse in vigilance, the endpoint security solution can then intervene where necessary.”

Tim Wade, Technical Director, CTO Team at Vectra, a San Jose, Calif.-based AI cybersecurity company, says, “Given the very tangible trade-offs associated with attempting mass decryption at scale across the enterprise, the key takeaway from such observations is that effective detection and response must itself be effective in the face of prevalent of encryption – it must anticipate encryption and maintain efficacy despite it.”