Cisco Talos, a renowned cybersecurity research team, has recently uncovered a new cyber threat targeting Mexican users. This campaign revolves around a previously unknown malware dubbed “TimbreStealer.” Let’s delve into the details:

The Malware and Its Origins

·      TimbreStealer: This sophisticated information-stealing malware specifically targets victims in Mexico. It operates by infiltrating victims’ systems and surreptitiously gathering sensitive data.

·      Threat Actor: The same threat actor responsible for TimbreStealer has a history of deploying similar tactics. They previously distributed a banking trojan known as “Mispadu.”

How TimbreStealer Works

1.   Phishing Lures: The campaign begins with phishing emails sent to potential victims. These emails exploit financial themes, enticing users to download a seemingly harmless file.

2.   Payload Activation: Once the user executes the downloaded file, TimbreStealer’s primary payload is activated. But before that, an orchestrator module meticulously examines files and registry keys to ensure the absence of any prior system infections.

3.   Data Harvesting: TimbreStealer’s payload is designed to harvest a wide range of data, including credential information, and checks for the presence of remote desktop software.

Overlaps with Mispadu

 Interestingly, Cisco Talos identified overlaps between the TimbreStealer campaign and a Mispadu spam campaign observed in September 2023.

The threat actor employs geofencing to target users in Mexico exclusively. Any attempts to access the payload from other locations result in a blank PDF file.

TimbreStealer poses a significant risk to Mexican users, emphasizing the importance of vigilance against cyber threats. Organizations and individuals should stay informed and take necessary precautions to safeguard their systems and sensitive data.