When I looked on recent public submissions on Any.Run this week, my attention was attracted by XWorm samples with tags “stegocampaign”. Quick review of analysis reports reveal simple, yet interesting infection chain. It contains Visual Basic script, PowerShell script, picture with Base64-encoded executable and the XWorm RAT itself. Those payloads have been downloaded from online hosting services such as Pastebin or Firebase. Moreover, they have been downloaded via HTTPs, so basic network analysis does not reveal the content nor the URL links, however, there are some simple methods how to reveal the real URLs.

AsyncRAT is an open source remote administration tool written in C#. It is often used by attackers for malicious purposes. It contains obfuscated and AES-encrypted strings in its configuration. In this blog post, I would like to describe my approach of decrypting those strings with CyberChef with leverage the power of Registers and other CyberChef features.

Attackers compromised up to 1500 companies during massive ransomware attack, which is now reported as one of the largest cyber attacks ever. Victims have been infected with REvil ransomware, which is similar to DarkSide ransomware used recently in Colonial Pipeline attack. However, this time, the deployed REvil ransomware was more obfuscated than versions observed in beginning of 2021. In this article, we will discuss the obfuscation techniques used by REvil in Kaseya incident.

DarkSide Ransomware is a very hot topic now, especially after the Compromise of Colonial Pipeline networks, which has been investigated by FBI, too. It caused so serious problems that even hackers said that they “didn’t mean to create problems”. However, DarkSide ransomware is not something completely new, and it is similar to the infamous Revil/Sodinokibi ransomware. In this post, I would like to highlight some significant similarities between newer samples of both ransomwares with insights about DarkSide victims based on custom ransom notes.

In June, LIFARS team worked on engagement related to FIN6 threat actor. FIN6 group was also detected and described in April and May, by various other forensics firms, including SentinelOne and FireEye Managed Defense (Mandiant), which described intrusion by FIN6 threat actor and their latest tactics, techniques, and procedures (TTPs). In particular, they used also LockerGoga and Ryuk ransomware families, and Cobalt Strike for initial compromise and lateral movement. Even three months after publishing their post, some of the URLs for Cobalt Strike stagers have been still active, so I decided to publish analysis of these Cobalt Strike stagers and payloads.