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What is Bumblebee Malware?


Bumblebee malware is a relatively new type of malware downloader that has been linked to several cybercriminal groups. It is unique because it can remain undetected on infected systems by hiding in plain sight. Bumblebee malware is also challenging to remove, which means it can cause a lot of damage before it is finally detected and removed. In this blog post, we will discuss what Bumblebee malware is, how it works, and some tips for protecting your system from infection.

What is Bumblebee malware? 

Bumblebee is a malware loader created to replace the BazarLoader backdoor, which has been used to deliver ransomware payloads. Built using the C++ programming language, Bumblebee’s code remains condensed in a single function that handles the initialization, deployment, heeding responses, and sending requests. The malware downloader's configuration is presently in plaintext, which may be hidden in the future to keep enterprising security professionals guessing.  

The emergence of Bumblebee has coincided with a steep decline in the use of other well-known malware loaders like IcedID and BazarLoader. According to an independent malware researcher Eli Salem, the creators of Bumblebee may be connected to the TrickBot botnet, primarily because of the similarities in their source code. Different antivirus programs call it by other names. For example:

  • Kaspersky terms it HEUR: Trojan.Win32.Generic

  • Microsoft Security (Program: Win32/Wacapew.C!ml)

  • Avast (LNK: Agent-BD [Trj])

  • ESET-NOD32 (Win64/Kryptik.CZJ)

  • Combo Cleaner (Gen: Variant.Lazy.164691)

Here is a list of other names that the Bumblebee malware goes by.

 What damage can Bumblebee do? 

The bumblebee malware works as a downloader to run cultivated malicious codes and help with loading Meterpreter, Shell-code injection, DLL injection, and Cobalt Strike. The compact nature of Bumblebee is likely to make it the preferred multifunctional tool for cybercriminals and threat actors. Bumblebee may be found in fraudulent emails, as was the case with DocuSign phishing, which attempted to entice victims by posing as coming from the e-signature solutions firm. It can also come as malicious HTML attachments or scam links that redirect the victim to a Microsoft OneDrive link that will have an ISO file containing the Bumblebee malware in the form of malicious shortcuts and DLLs files.  

The threat actors behind the Bumblebee malware downloader are known to infiltrate different systems and sell access to and data of exploited computers. Independent malware researcher Eli Salem also added that, like TrickBot, Bumblebee malware also uses a web-inject module & has the same evasion technique.  

How to safeguard your enterprise against Bumblebee malware

Prevention is always better than cure. Following cybersecurity hygiene and best practices is the best way to protect your business from any malware. Here are some recommended best practices:

  • Use anti-malware and anti-spyware

Enterprise systems should have regularly updated and patched anti-malware and anti-spyware programs that can easily detect any malware. Combo Cleaner, EST NOD-32, Fortinet, and Comodo are some antivirus and anti-malware programs that can detect the Bumblebee malware. 

  • Use administrative account if necessary

Bumblebee malware can leverage administrative privileges to access or exploit other computer parts. It is recommended not to download anything suspicious through email via administrative accounts. Employees and IT professionals should log in to administrative accounts only to perform privileged tasks like giving someone user access or changing configuration. 

  • Limit application privileges and adhere to the least-privilege principle 

Enterprises should follow the "principle of least privileges" and grant employees minimum system requirements and usability. Also, not everyone should get permission to download and execute any file from the internet. 

  • Educate employees

Enterprises should educate employees on the latest malware and how they behave or attack a system. Also, enterprises should train them not to download files and email attachments from unknown emails, malicious links, or unofficial sites.


Bumblebee is quickly becoming the preferred tool for cybercriminals looking to steal and leverage data. Enterprises should take steps to protect themselves against this malware and educate their employees on the latest malware threats.