Trojan.MSIL.TNEGA.0NA104F923

June 21, 2023
 Analysis by: Francesca Villasanta
 ALIASES:

Trojan:MSIL/Tnega.RVA (MICROSOFT); UDS:Backdoor.MSIL.NanoBot.gen (KASPERSKY)

 PLATFORM:

Windows

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 REPORTED INFECTION:
 INFORMATION EXPOSURE:

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Downloaded from the Internet, Dropped by other malware

This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

It deletes the initially executed copy of itself.

  TECHNICAL DETAILS

File Size:

59,392 bytes

File Type:

Other

Memory Resident:

No

Initial Samples Received Date:

09 Jun 2023

Payload:

Connects to URLs/IPs, Deletes files

Arrival Details

This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

Installation

This Trojan adds the following processes:

  • %System%\WindowsPowerShell\v1.0\powershell.exe" -ENC {Base64 Encoded Command}
  • %System%\WindowsPowerShell\v1.0\powershell.exe" -ENC {Another Base64 Encoded Command}

(Note: %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)

Other Details

This Trojan connects to the following possibly malicious URL:

  • http://{BLOCKED}.{BLOCKED}.{BLOCKED}.42/Rlncpcrkhuy.dll

It deletes the initially executed copy of itself.

  SOLUTION

Minimum Scan Engine:

9.800

FIRST VSAPI PATTERN FILE:

18.510.01

FIRST VSAPI PATTERN DATE:

15 Jun 2023

VSAPI OPR PATTERN File:

18.511.00

VSAPI OPR PATTERN Date:

16 Jun 2023

Step 1

Before doing any scans, Windows 7, Windows 8, Windows 8.1, and Windows 10 users must disable System Restore to allow full scanning of their computers.

Step 2

Scan your computer with your Trend Micro product to delete files detected as Trojan.MSIL.TNEGA.0NA104F923. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check the following Trend Micro Support pages for more information:


Did this description help? Tell us how we did.