Beware of BundleBot: The .NET single-file malware that’s stealing information of unsuspecting users

Beware of BundleBot: The .NET single-file malware that's stealing information of unsuspecting users

Introducing the newest cyber threat: BundleBot! This malware strain has been flying under the radar, exploiting .NET single-file deployment techniques to infiltrate and compromise unsuspecting hosts. What’s even more alarming is that it can silently seize sensitive information from compromised hosts.

BundleBot Infection Tactic

Recent findings by cybersecurity experts at Check Point have unveiled the alarming tactics deployed by BundleBot to deceive its victims.

In a report published this week, Check Point said “BundleBot is abusing the dotnet bundle (single-file), a self-contained format that results in very low or no static detection at all”. adding that “the typical initial vector of infection points to Facebook Ads or compromised accounts leading to websites masquerading as regular program utilities”.

Some of these websites impersonate Google Bard, the renowned conversational generative AI chatbot from Google. Their ultimate goal? To lure unsuspecting victims into downloading a fraudulent RAR archive named “Google_AI.rar.”

To add an extra layer of deceit, these archives are hosted on legitimate cloud storage platforms like Dropbox. These crafted websites closely mimic the appearance and functionality of the genuine Google Bard, luring victims into a false sense of security.

Once the archive file is unzipped, it contains an executable file named “GoogleAI.exe”, a devious .NET single file, a self-contained application that incorporates another DLL file named “GoogleAI.dll.”

The sole purpose of this DLL is to download a password-protected ZIP archive from Google Drive.

BundleBot Infection Stages

Once the ZIP file, bearing the name “,” is downloaded and unzipped, another potent .NET single-file, a self-contained application known as “RiotClientServices.exe” is revealed. This file incorporates the notorious BundleBot payload (“RiotClientServices.dll”) and a crafty command-and-control (C2) packet data serializer named “LirarySharing.dll.”

The binary artifacts of this payload employ bespoke obfuscation and junk code designed to thwart analysis and elude detection. Within it lies a host of capabilities, enabling this malicious entity to carry out its sinister objectives.

“These binaries are affected by similar custom-made obfuscation that mainly focuses on name obfuscation and bloating those dotnet modules with a lot of junk code”. the Israeli cybersecurity company said. Adding that “Such an obfuscation will result in an overwhelming number of methods and classes that will make the analysis much harder and require creating a custom deobfuscator to simplify the analysis process.”

According to Check Point, they also identified a second sample of BundleBot, which bears an almost identical resemblance to the first, except for one key distinction: the absence of HTTPS for information exfiltration. Instead, this variant transmits data to a remote server using a ZIP archive format.

Read Also: Why Do Some Websites Start with ‘www.’ and Others with ‘ww1’?

Staying Safe in the Face of Evolving Cyber Threats

As the digital world continues to evolve, so do the tactics employed by cybercriminals seeking to exploit our vulnerabilities.

To safeguard ourselves against such threats, it’s crucial to be proactive and vigilant in our cybersecurity practices. Here’s a summary of essential safety measures to keep in mind:

Beware of Impersonations: Cybercriminals are masters of disguise, using fake websites to mimic trusted entities like Google Bard. Be cautious when encountering unsolicited files or links, especially those hosted on legitimate cloud services.

Be Wary of Archive Files: Exercise caution when dealing with archive files like RAR or ZIP, especially if they prompt you to download and run executable files. Verify the source and legitimacy of the files before proceeding.

Stay Informed and Updated: Regularly update your software, operating systems, and security tools to ensure you have the latest protection against emerging threats.

Exercise Caution Online: Be skeptical of enticing offers, particularly via social media or suspicious advertisements. Think twice before downloading unfamiliar extensions or software from unknown sources.

Use HTTPS and Secure Connections: Whenever possible, opt for websites and applications that use HTTPS encryption to safeguard your data during transmission.

Secure Your Accounts: Enable multi-factor authentication (MFA) for your online accounts, especially on platforms like Facebook and Discord, to add an extra layer of security.

Implement Robust Security Measures: Employ strong and unique passwords for each account, and consider using a reputable password manager to help you keep track of them securely.

Stay Updated on Cyber Threats: Keep yourself informed about the latest cyber threats and scams. Regularly review security reports and advisories from trusted sources to understand the risks and potential vulnerabilities.

Educate Yourself and Others: Educate yourself and your loved ones about common cyber threats and how to spot suspicious activities online. Awareness is a powerful defense against cyberattacks.

Backup Your Data: Regularly back up your important files and data to a secure location, so even if you fall victim to a cyberattack, you won’t lose critical information.

By adhering to these safety measures and maintaining a proactive approach to cybersecurity, you can fortify your online defenses and navigate the digital landscape with confidence. Together, we can stay one step ahead of cyber adversaries and protect our valuable digital assets from the clutches of these digital malefactors. Stay informed, stay secure, and stay resilient in the face of ever-evolving cyber threats.

Stay vigilant and don’t let the mirage of authenticity lead you astray!

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