Discovered in Russia: The Malicious Efimer Virus - A Thief of Funds by Kaspersky Lab
The cybersecurity landscape is once again under threat, as experts from Kaspersky Lab report that Efimer campaigns are ongoing. This Trojan, first detected in October 2024, has been causing concern due to its stealthy yet destructive nature.
The malicious software, related to the Efimer Trojan, has been detected in Russia. It is capable of stealing financial assets, replacing cryptocurrency wallets, and collecting passwords for websites. Cybercriminals employ a multi-vector distribution strategy, targeting both individual and corporate users.
For regular users, torrent files disguised as popular movies are used as bait, while for companies, phishing emails are sent. The emails do not provide details of the violation or offers for purchase; these can supposedly be found by opening the attachment. The malicious files, hidden within password-protected archives, install the Efimer Trojan on the system once launched.
The Trojan operates primarily as a cryptocurrency stealer, distributed through compromised WordPress websites, phishing emails with malicious ZIP attachments, and torrent files. It communicates with its command-and-control (C2) server over the TOR network.
Efimer's capabilities include stealing cryptocurrency by replacing wallet addresses copied to the clipboard, brute-forcing WordPress passwords, harvesting email addresses from websites to expand phishing campaigns, and using the infected host to send spam via website contact forms.
Kaspersky Lab's products successfully detect and protect users from various modifications of Efimer, including those functioning as a dropper, banking Trojan, and spyware. The company suggests several countermeasures against Efimer, including rigorous WordPress site security, caution with unexpected emails, robust email filtering and endpoint security, analysis of suspicious script files in a sandbox environment, and keeping antivirus definitions up to date.
As the Efimer Trojan continues to evolve and spread, it is crucial for individuals and businesses to stay vigilant and follow best practices for cybersecurity. By doing so, we can help prevent the theft of valuable financial assets and maintain the security of our digital world.
[1] Press service of Kaspersky Lab [2] Cybersecurity Intelligence Report, June 2025 [3] The Hacker News, July 2025 [4] TechRadar, August 2025
- Amidst the ongoing Efimer campaigns, concerns arise in the field of science and technology, as the malicious software poses a threat to cybersecurity, stealing financial assets and passwords for websites.
- The evolving nature of Efimer Trojan, a notorious threat in the cybersecurity landscape, underscores the significance of integrating robust security measures in finance and technology industries to safeguard valuable digital assets from espionage and theft.
