A relatively new malware variant dubbed Latrodectus is increasingly being used to gain initial access to business networks. Latrodectus is the Latin for Widow spiders, but the malware was so named because of a line in the code that mentions the word. The malware was first detected in November 2023, and detections have been increasing ever since, especially since February 2024. Analyses of Latrodectus malware have revealed strong similarities with the IcedID remote access trojan (RAT) and malware loader, and the infrastructure that supports the malware was previously used in IcedID campaigns. That strongly suggests that Latrodectus malware is the successor of IcedID and was most likely developed by the same threat actor.

Latrodectus malware is primarily a malware downloader and backdoor that is used to deliver a range of different payloads and execute commands on an infected device. Latrodectus is a modular malware capable of adapting to different environments, has extensive capabilities, is stealthy, and can bypass many cybersecurity solutions.  The malware checks for the presence of debuggers, has anti-sandbox capabilities and encrypts communications with its C2 server. The malware gains persistence via auto-run keys and scheduled tasks.

Latrodectus malware is believed to be used by highly capable threat actors that specialize in gaining initial access to networks to sell on to other threat actors such as ransomware groups. The malware is primarily distributed in phishing emails, with the detected emails so far using Microsoft Azure and Cloudflare-themed lures, with either PDF file attachments or URLs embedded in emails. The malware has also been identified as being distributed via contact form spam.

If the PDF files are opened, the user is told that the document has been uploaded to the Microsoft Azure Cloud and they are required to download it. The user is then directed to a fake Cloudflare security check that adds legitimacy but also prevents email security solutions from following the link and prevents in-depth analysis in sandboxes. If the user proceeds, they will download a JavaScript file that appears to be the document indicated in the PDF file. If the file is executed, a script runs that downloads an MSI installer, which drops and executes the Lactrodectus DLL.

Due to the evasive capabilities of the malware, standard email security solutions are unlikely to identify the phishing emails as malicious, and even email sandboxing checks may be passed. An advanced anti-spam service is required that incorporates AI- and machine learning capabilities to identify the malicious nature of the email. SpamTitan Plus is an advanced email security solution with the highest coverage of anti-phishing feeds of any product on the market, incorporating coverage of 100% of all current market-leading anti-phishing feeds. The superior threat intelligence fed into the system and massive clickstream traffic from more than 600 million users and endpoints ensure the URLs used to deliver malware are detected and blocked. The machine learning capabilities of SpamTitan Plus allow the solution to predict and block novel phishing campaigns, including phishing attacks that use personalized URLs when targeting individuals. URLs are followed and are rewritten to identify the destination, and the solution features time-of-click protection to identify and block URLs that are weaponized after delivery.

As an additional protection, businesses should consider a web filtering solution. WebTitan from TitanHQ protects against the web-based component of cyberattacks. While SpamTitan Plus can block attempts to visit URLs embedded in emails and email attachments, WebTitan will block visits to URLs from general web browsing, redirects from malvertising, and non-email communications. WebTitan can also be configured to block downloads of files from the Internet associated with malware – JavaScript files for instance.

End-user training is also important to teach cybersecurity best practices and eliminate risky behaviors. SafeTitan is a comprehensive security awareness training platform with hundreds of training modules that can be easily configured to create and automate training courses relevant to individuals and user groups. The platform includes a phishing simulator for conducting realistic phishing simulations, using messages that have been created from genuine phishing attacks. The platform is the only behavior-driven security awareness training platform that delivers training in real time in response to simulation failures and security mistakes.

As cyber threats increase in sophistication, multiple cybersecurity solutions are required to provide multi-layered protection. TitanHQ solutions will ensure you are well protected from ever-changing cyber threats and sophisticated phishing and malware attacks.