Trojan.X97M.ASYNCRAT.C
Trojan:Win32/Leonem (MICROSOFT); UDS:DangerousObject.Multi.Generic (KASPERSKY)
Windows
Threat Type: Trojan
Destructiveness: No
Encrypted:
In the wild: Yes
OVERVIEW
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.
As of this writing, the said sites are inaccessible.
TECHNICAL DETAILS
404,992 bytes
XLS
No
24 Apr 2023
Connects to URLs/IPs, Displays graphics/image, Drops 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 drops and executes the following files:
- %Application Data%\nnss.exe
(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Roaming on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)
It adds the following processes:
- %Application Data%\nnss.exe
(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Roaming on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)
Download Routine
This Trojan connects to the following website(s) to download and execute a malicious file:
- https://www.{BLOCKED}randinas.com/cscontent/content1/djbjgbkbfdffdfgvbhbfndghfn.exe
It saves the files it downloads using the following names:
- %Application Data%\nnss.exe
(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Roaming on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)
As of this writing, the said sites are inaccessible.
Other Details
This Trojan does the following:
- It displays the following to lure users into enabling macro content:
It does not exploit any vulnerability.
SOLUTION
9.800
18.406.01
25 Apr 2023
18.407.00
26 Apr 2023
Step 1
Trend Micro Predictive Machine Learning detects and blocks malware at the first sign of its existence, before it executes on your system. When enabled, your Trend Micro product detects this malware under the following machine learning name:
-
Downloader.VBA.TRX.XXVBAF01FF040
Step 2
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 3
Note that not all files, folders, and registry keys and entries are installed on your computer during this malware's/spyware's/grayware's execution. This may be due to incomplete installation or other operating system conditions. If you do not find the same files/folders/registry information, please proceed to the next step.
Step 4
Search and delete this file
- %Application Data%\nnss.exe
Step 5
Scan your computer with your Trend Micro product to delete files detected as Trojan.X97M.ASYNCRAT.C. 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:
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