Threat Descriptions

Backdoor:W32/Nanocore

Classification

Category :

Malware

Type :

Backdoor

Platform :

W32

Aliases :

Backdoor:W32/Nanocore

Summary

This threat is a Remote Access Tool (RAT) that allows the infected system to be remotely controlled and monitored by malicious actors.

Removal

Based on the settings of your F-Secure security product, it will either move the file to the quarantine where it cannot spread or cause harm, or remove it.

A False Positive is when a file is incorrectly detected as harmful, usually because its code or behavior resembles known harmful programs. A False Positive will usually be fixed in a subsequent database update without any action needed on your part. If you wish, you may also:

  • Check for the latest database updates

    First check if your F-Secure security program is using the latest updates, then try scanning the file again.

  • Submit a sample

    After checking, if you still believe the file is incorrectly detected, you can submit a sample of it for re-analysis.

    NOTE If the file was moved to quarantine, you need to collect the file from quarantine before you can submit it.

  • Exclude a file from further scanning

    If you are certain that the file is safe and want to continue using it, you can exclude it from further scanning by the F-Secure security product.

    Note You need administrative rights to change the settings.

Technical Details

Infection Vector

This threat is the payload of a multi-stage trojan-downloader, which usually arrives as a document file attached to email messages sent out as part of a spam email campaign.

Behavior

This RAT is used for surveillance and data exfiltration.

It remains persistent in the system by installing the Run registry and Scheduled tasks to execute itself during startup.

Autorun Keys:

  • Name: "SAAS Monitor"
  • Data: "c:\program files\saas monitor\saasmon.exe"

Scheduled Tasked:

  • \SAAS Monitor <%Malware Path%>
  • Example: \SAAS Monitor Task c:\program files\saas monitor\saasmon.exe

To protect its process, the RAT throws an exception which will cause the system to crash when its process is terminated.

This threat establishes a connection to a remote command-and-control (C&C) server and executes the command(s) issued by the C&C server.
It provides the following details to the C&C server:

System information
  • Current active window
  • CPU Usage
  • RAM Usage
  • PING
  • Client country
  • Workstation name
  • Idle time
  • OS
  • OS bit
  • Access rights
  • Anti-Virus application
  • Anti-Spyware application
  • Firewall application

This threat is capable to execute these function on the infected system when connected to the C&C server:

  1. Connection
    • Restart, Disconnect, Delete, and Uninstall
  2. Reboot and Shutdown
  3. Access system utilities
    • Task Manager
    • Registry Editor
    • Remote Console / CMD
    • Open File Browser / File Explorer
      • Read, Write, Delete, Import and Export
  4. Stealer:
    • Password recovery
    • DNS Record
    • Keylogger
    • Video and Screen Feeds
    • Audio Feeds
  5. Other functions:
    • Instant message from C&C
    • Remote Execution from local or web
    • Update RAT Client from local or web
    • Flush memory or Processes
    • Trigger elevation request

Analysis on file: bc86b20a3ce153698961b318399943f795a2a1b3