A new information stealer malware is quickly becoming popular among hackers on prominent underground forums, according to a warning from cybersecurity company Cyfirma.
Dubbed Mystic Stealer, the malware was first spotted in April 2023 when it was made available to seasoned cybercriminals for testing purposes.
Cyfirma’s researchers tracking the evolution of the malware discovered that the developer updated the information stealer based on feedback, leading to a surge in prevalence, with more than 50 active command-and-control (C&C) servers identified to date.
Written in C and targeting Windows, Mystic Stealer leverages code manipulation and operates in memory to evade detection. The malware uses system calls to compromise targets and to avoid leaving evidence of infection behind.
The malware does not use third-party libraries, contains a self-written browser database parser, and was designed to search for data of interest before compression, encryption and exfiltration.
Mystic Stealer’s developer also provides cybercriminals with a builder to deploy on their own server in order to customize the malware for attacks. A C&C panel provides Mystic Stealer users with control over the malware and the data gathering process.
According to Cyfirma, the malware is capable of hijacking passwords, cookies, credit cards, and other information from browsers and cryptocurrency wallet extensions, Outlook passwords, and files, and can take screenshots and gather system information.
A sophisticated malware evolving based on recommendations received from well-known cybercriminals, Mystic Stealer has the potential of becoming a major threat to companies handling personally identifiable information (PII) and financial records, including healthcare, finance, and technology firms.
“Along with that, Mystic Stealer specifically targets individuals involved in cryptocurrency transactions. This includes users of cryptocurrency wallets, traders, and those engaged in mining activities. The malware aims to steal cryptocurrency wallets, private keys, or login credentials to gain unauthorized access to these assets,” Cyfirma notes.