Endpoint malware and ransomware detections hit all-time high

Endpoint malware and ransomware detections surpassed the total volume seen in 2020 by the end of Q3 2021, according to researchers at the WatchGuard Threat Lab. In its latest report, WatchGuard also highlights that a significant percentage of malware continues to arrive over encrypted connections.

While zero-day malware increased by just 3% to 67.2% in Q3 2021, the percentage of malware that arrived via Transport Layer Security (TLS) jumped from 31.6% to 47%. Data shows that many organizations are not decrypting these connections and therefore have poor visibility into the amount of malware hitting their networks.

“While the total volume of network attacks shrank slightly, malware per device was up for the first time since the pandemic began,” said Corey Nachreiner, CSO at WatchGuard. “The security environment continues to be challenging, so it’s important that organizations go beyond the short-term ups and downs and seasonality of specific metrics and focus on persistent and concerning trends factoring into their security posture. An important example is the accelerating use of encrypted connections to deliver zero days.”

Additional findings on endpoint malware and ransomware detections

As users upgrade to more recent versions of Microsoft Windows and Office, attackers are focusing on newer vulnerabilities – While unpatched vulnerabilities in older software continue to provide a rich hunting ground for attackers, they are also looking to exploit weaknesses in the latest versions of Microsoft’s widely used products. In Q3, CVE-2018-0802 – which exploits a vulnerability in the Equation Editor in Microsoft Office – cracked WatchGuard’s top 10 gateway antivirus malware by volume list, hitting number 6, after showing up in the most-widespread malware list in the previous quarter. In addition, two Windows code injectors (Win32/Heim.D and Win32/Heri) came in at number 1 and 6 on the most detected list respectively.

Attackers disproportionately targeted the Americas – The overwhelming majority of network attacks targeted the Americas in Q3 (64.5%) compared to Europe (15.5%) and APAC (20%).

Overall network attack detections resumed a more normal trajectory but still pose significant risks – After consecutive quarters of more than 20% growth, roughly 4.1 million unique network exploits were detected in Q3. The drop of 21% brought volumes down to Q1 levels, which were still high compared to the previous year. The shift doesn’t necessarily mean adversaries are letting up as they are possibly shifting their focus towards more targeted attacks.

The top 10 network attack signatures account for the vast majority of attacks – Of the 4,095,320 hits detected by IPS in Q3, 81% were attributed to the top 10 signatures. In fact, there was just one new signature in the top 10 in Q3, ‘WEB Remote File Inclusion /etc/passwd’ (1054837), which targets older, but still widely used Microsoft Internet Information Services (IIS) web servers. One signature (1059160), a SQL injection, has continued to maintain the position it has held atop the list since Q2, 2019.

Scripting attacks on endpoints continue at record pace – By the end of Q3, there were already 10% more attack scripts than in all of 2020, which, in turn, saw a 666% increase over the prior year. As hybrid workforces start to look like the rule rather than the exception, a strong perimeter is no longer enough to stop threats.

While there are several ways for cybercriminals to attack endpoints – from application exploits to script-based living-off-the-land attacks – even those with limited skills can often fully execute a malware payload with scripting tools like PowerSploit, PowerWare and Cobalt Strike, while evading basic endpoint detection.

Even normally safe domains can be compromised – A protocol flaw in Microsoft’s Exchange Server Autodiscover system allowed attackers to collect domain credentials and compromise several normally trustworthy domains. Overall, in Q3 5.6 million malicious domains were blocked , including several new malware domains that attempt to install software for cryptomining, key loggers and remote access trojans (RATs), as well as phishing domains masquerading as SharePoint sites to harvest Office365 login credentials.

While down 23% from the previous quarter, the number of blocked domains is still several times higher than the level seen in Q4 2020 (1.3 million). This highlights the critical need for organizations to focus on keeping servers, databases, websites, and systems updated with the latest patches to limit vulnerabilities for attackers to exploit.

Ransomware, ransomware, ransomware – After a steep decline in 2020, ransomware attacks reached 105% of 2020 volume by the end of September, as predicted at the end of the prior quarter and are on pace to reach 150% once the full year of 2021 data is analysed. Ransomware-as-a-service operations such as REvil and GandCrap continue to lower the bar for criminals with little or no coding skills, providing the infrastructure and the malware payloads to carry out attacks globally in return for a percentage of the ransom.

The quarter’s top security incident, Kaseya, was another demonstration of the ongoing threat of digital supply chain attacks – Just before the start of the long 4th of July holiday weekend in the US, dozens of organizations began reporting ransomware attacks against their endpoints. WatchGuard’s incident analysis described how attackers working with the REvil ransomware-as-a-service (RaaS) operation had exploited three zero-day vulnerabilities (including CVE-2021-30116 and CVE-2021-30118) in Kaseya VSA Remote Monitoring and Management (RMM) software to deliver ransomware to some 1,500 organizations and potentially millions of endpoints.

While the FBI eventually compromised REvil’s servers and obtained the decryption key a few months later, the attack provided yet another stark reminder of the need for organizations to proactively take steps like adopting zero-trust, employing the principle of least privilege for vendor access and ensuring systems are patched and up to date to minimize the impact of supply chain attacks.