Researchers uncovered a new malspam campaign through which cyber criminals launching Zeus Sphinx Malware via Coronavirus Lure Malformed MS documents.
Since the novel Coronavirus pandemic rapidly spreading country to country, threat actors taking advantage of the trending news to tempting victims and attack their systems with the large scale of malspam campaign.
Researchers from IBM X-FORCE observed the Zeus Sphinx Malware activities in 2019, since then the activities of this campaign rapidly increased and they are mainly targeting the government relief payments and also continue to focus bank sectors in US, Canada, and Australia.
Maldoc Spam Delivery
Cybercriminals taking advantage of trending COVID-19 theme to distributing the Malformed MS word document through phishing, spam campaign.
Spam email urge victims to open the attachment and fill the document to receive the compensation from the Government, and they are distributing a variety of documents and the majority of documents with .doc or .docx files
Later the document request victims to enable executing a macro to trigger the infection chain and ended up hijacking the windows process to fetch the malware downloader.
The malware downloader then communication with the command and control server to fetch the new Zeus Sphinx malware payload.
New Zeus Sphinx variant starts off with the weaponized document that creates a malicious folder under %SYSTEMDRIVE% and writes a batch file into it.
According to the IBM report ” Once on the device, Sphinx establishes persistence via commonly used methods to maintain its grasp on the end user’s machine. In this case, it writes numerous folders and files to disk and adds some Registry keys in order to hide and manage its configuration files over time. “
Sphinx also capable of collecting the online account credentials from banks and a wide range of other websites using a web injection technique that has inherited from its Zeus v2 codebase.
Indicators of Compromise (IoCs)
VBS sample: 2FC871107D46FA5AA8095B78D5ABAB78