BlackByte Ransomware Operation Overview

Starting in July 2021, BlackByte, a ransomware operation, began targeting corporate victims across the globe. Victims first discovered the group when they needed assistance decrypting their files. BlackByte, a Russian-based ransomware group, operates on a ransomware-as-a-service (RaaS) model and uses double-extortion tactics to compel victims to pay. Within their initial year, the Federal Bureau of Investigation (FBI) and the US Secret Service (USS) took notice of BlackByte's activities and issued a joint advisory warning about the group.

Early Operations and Attention

BlackByte initially operated with limited activity. Early reports indicated that BlackByte's level of activity was not as high as other ransomware operations, but it attracted the attention of researchers. Their ransomware capabilities did not pose the most significant threat. In the previous version of BlackByte, the same key was utilized for file encryption in every campaign. The group employed AES, a symmetric key algorithm, enabling researchers to develop a decrypter to assist victims affected by BlackByte.

Evolution of Encryption Tactics

Consequently, the group modified their encryption approach in newer versions. Around February 2022, they transitioned from C# to GoLang. This trend aligns with ransomware groups opting for programming languages like GoLang and Rust, which have limited familiarity. This choice makes static analysis more challenging compared to commonly used programming languages like C#. Security products have long relied on signatures from well-known languages, making the analysis of different language signatures considerably more difficult.