We recently came across a stealer, called Raccoon Stealer, a name given to it by its author. Raccoon Stealer uses the Telegram infrastructure to store and update actual C&C addresses. Raccoon Stealer is a password stealer capable of stealing not just passwords, but various types of data...
Avast Releases Decryptor for the Prometheus Ransomware. Prometheus is a ransomware strain written in C# that inherited a lot of code from an older strain called Thanos. Skip to how to use the Prometheus ransomware decryptor. How Prometheus Works Prometheus tries to thwart malware analysis by...
On February 24th, the Avast Threat Labs discovered a new ransomware strain accompanying the data wiper HermeticWiper malware, which our colleagues at ESET found circulating in the Ukraine. Following this naming convention, we opted to name the strain we found piggybacking on the wiper...
On January 25, 2022, a victim of a ransomware attack reached out to us for help. The extension of the encrypted files and the ransom note indicated the TargetCompany ransomware (not related to Target the store), which can be decrypted under certain circumstances. Modus Operandi of the TargetCompany...
Introduction On September 15, 2021 the National Games of China began in the Chinese city of Shaanxi. It is an event similar if not identical to the Olympics, but only hosts athletes from China. Earlier in September, our colleague David Álvarez found a malware sample with a suspicious file extension...
Foreword Welcome to the Avast Q4’21 Threat Report! Just like the rest of last year, Q4 was packed with many surprises and plot twists in the threat landscape. Let me highlight some of them. We all learned how much impact a small library for logging can have. Indeed, I’m referring to the Log4j Java...
Chaes, a threat group operates solely in Brazil, compromised hundreds of WordPress webpages to serve malicious installers which is the starting point of an interesting infection chain.
In this posting, we go over what web skimming attacks are and how they work. We then analyze a series of web skimming attacks that we found which were active from March 2021 to the present. These attacks abused the Google Tag Manager...
Avast has found a targeted attack on a small US federal government commission. Despite the fact that they did not cooperate with us, we were able to analyze two files involved in this attack.
CoinHelper is a family of AutoIt droppers which provides a massive coinmining campaign. The malware is being spread in a form of a bundle with another software, being it game cheats, cracked software, or even clean installers such as Google Chrome, Microsoft Office, AV products, and many others.