Threat Roundup for February 28 to March 6

Glimpse into the most prevalent threats we’ve observed between Feb 28 and Mar 6.

Cisco Talos Intelligence Group is one of the largest commercial threat intelligence teams in the world, comprised of world-class researchers, analysts and engineers. These teams are supported by unrivalled telemetry and sophisticated systems to create accurate, rapid and actionable threat intelligence for Cisco customers, products and services. Talos defends Cisco customers against known and emerging threats, discovers new vulnerabilities in common software, and interdicts threats in the wild before they can further harm the internet at large. Talos maintains the official rule sets of Snort.org, ClamAV, and SpamCop, in addition to releasing many open-source research and analysis tools.

Talos is publishing a glimpse into the most prevalent threats we've observed between Feb. 28 and March 6. As with previous roundups, this post isn't meant to be an in-depth analysis. Instead, this post will summarize the threats we've observed by highlighting key behavioural characteristics, indicators of compromise, and discussing how our customers are automatically protected from these threats.

As a reminder, the information provided for the following threats in this post is non-exhaustive and current as of the date of publication. Additionally, please keep in mind that IOC searching is only one part of threat hunting. Spotting a single IOC does not necessarily indicate maliciousness. Detection and coverage for the following threats is subject to updates, pending additional threat or vulnerability analysis. For the most current information, please refer to your Firepower Management Center, Snort.org, or ClamAV.net.

For each threat described below, this blog post only lists 25 of the associated file hashes and up to 25 IOCs for each category. An accompanying JSON file can be found here that includes the complete list of file hashes, as well as all other IOCs from this post. As always, please remember that all IOCs contained in this document are indicators, and one single IOC does not indicate maliciousness.
The most prevalent threats highlighted in this roundup are:
THREAT NAMETYPEDESCRIPTION

Win.Dropper.Emotet-7600941-0	Dropper	Emotet is one of the most widely distributed and active malware families today. It is a highly modular threat that can deliver a wide variety of payloads. Emotet is commonly delivered via Microsoft Office documents with macros, sent as attachments on malicious emails.
Win.Downloader.Upatre-7601201-0	Downloader	Upatre is a malicious downloader often used by exploit kits and phishing campaigns. Upatre downloads and executes malicious executables, such as banking malware.
Win.Malware.Kovter-7601670-0	Malware	Kovter is known for its fileless persistence mechanism. This family of malware creates several malicious registry entries which store its malicious code. Kovter is capable of reinfecting a system, even if the file system has been cleaned of the infection. Kovter has been used in the past to spread ransomware and click-fraud malware.
Win.Malware.Trickbot-7603048-1	Malware	Trickbot is a banking trojan targeting sensitive information for certain financial institutions. This malware is frequently distributed through malicious spam campaigns. Many of these campaigns rely on downloaders for distribution, such as VB scripts.
Win.Malware.Nymaim-7602109-1	Malware	Nymaim is malware that can be used to deliver ransomware and other malicious payloads. It uses a domain generation algorithm to generate potential command and control (C2) domains to connect to additional payloads.
Win.Packed.Bifrost-7603033-1	Packed	Bifrost is a backdoor with more than 10 variants. Bifrost uses the typical server, server builder, and client backdoor program configuration to allow a remote attacker, who uses the client, to execute arbitrary code on the compromised machine. Bifrost contains standard RAT features including a file manager, screen capture utility, keylogging, video recording, microphone and camera monitoring, and a process manager. Bifrost uses a mutex that may be named "Bif1234," or "Tr0gBot" as signs that it's been successful.
Win.Packed.Tofsee-7603095-1	Packed	Tofsee is multi-purpose malware that features a number of modules used to carry out various activities such as sending spam messages, conducting click fraud, mining cryptocurrency, and more. Infected systems become part of the Tofsee spam botnet and are used to send large volumes of spam messages in an effort to infect additional systems and increase the overall size of the botnet under the operator's control.
Win.Ransomware.Nemty-7603722-1	Ransomware	Nemty is ransomware that encrypts files and demands payment in Bitcoin for files to be recovered.
Win.Trojan.Gh0stRAT-7603864-1	Trojan	Gh0stRAT is a well-known family of remote access trojans designed to provide an attacker with complete control over an infected system. Capabilities include monitoring keystrokes, collecting video footage from the webcam, and uploading/executing follow-on malware. The source code for Gh0stRAT has been publicly available on the Internet for years, significantly lowering the barrier for actors to modify and reuse the code in new attacks.

Access the complete THREAT BREAKDOWN