A spam email campaign is being conducted targeting corporate email accounts to distribute Loki Bot malware. Loki Bot malware is an information stealer capable of obtaining passwords stored in browsers, obtaining email account passwords, FTP client logins, cryptocurrency wallet passwords, and passwords used for messaging apps.
In addition to stealing saved passwords, Loki Bot malware has keylogging capabilities and is potentially capable of downloading and running executable files. All information captured by the malware is transferred to the attacker’s C2 server.
Kaspersky Lab researchers identified an increase in email spam activity targeting corporate email accounts, with the campaign discovered to be used to spread Loki Bot malware. The malware was delivered hidden in a malicious email attachment.
The intercepted emails included an ICO file attachment. ICO files are copies of optical discs, which are usually mounted in a virtual CD/DVD drive to open. While specialist software can be used to open these files, most modern operating systems have the ability to access the contents of the files without the need for any additional software.
In this case, the ICO file contains Loki Bot malware and double clicking on the file will result in installation of the malware on operating systems that support the files (Vista and later).
It is relatively rare for ICO files to be used to deliver malware, although not unheard of. The unfamiliarity with ICO files for malware delivery may see end users attempt to open the files.
The campaign included a wide range of lures including fake purchase orders, speculative enquiries from companies containing product lists, fake invoices, bank transfer details, payment requests, credit notifications, and payment confirmations. Well-known companies such as Merrill Lynch, Bank of America, and DHL were spoofed in some of the emails.
Spam Email Campaign Distributing Marap Malware Targets Financial Institutions
A separate and unrelated spam email campaign has been identified that is using IQY files to deliver a new form of malware known as Marap. Marap malware is a downloader capable of downloading a variety of different payloads and additional modules.
Upon installation, the malware fingerprints the system and gathers information such as username, domain name, IP address, hostname, language, country, Windows version, details of Microsoft .ost files, and any anti-virus solutions detected on the infected computer. What happens next depends on the system on which it is installed. If the system is of particular interest, it is earmarked for a more extensive compromise.
Four separate campaigns involving millions of messages were detected by researchers at Proofpoint. One campaign included an IQY file as an attachment, one included an IQY file within a zip file and a third used an embedded IQY file in a PDF file. The fourth used a Microsoft Word document containing a malicious macro. The campaigns appear to be targeting financial institutions.
IQY files are used by Excel to download web content directly into spreadsheets. They have been used in several spam email campaigns in recent weeks to install a variety of different malware variants. The file type is proving popular with cybercriminals because many anti-spam solutions fail to recognize the files as malicious.
Since the majority of end users would not have any need to open ICO or IQY files, these file types should be added to the list of blocked file types in email spam filters to prevent them from being delivered to end users’ inboxes.