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.
However, as of this writing, the said sites are inaccessible.
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 folders:
(Note: %System Root% is the Windows root folder, where it usually is C:\ on all Windows operating system versions.)
It drops the following files:
- %System Root%\MyMusic\presskey.cmd → executes %System Root%\MyMusic\presskey.jse
- %System Root%\MyMusic\presskey.jse → Detected as Worm.JS.JASCREX.B
(Note: %System Root% is the Windows root folder, where it usually is C:\ on all Windows operating system versions.)
It adds the following processes:
- cmd/T: /U /Q /C cd /D {Drive Letter}: && dir /b/s/x *.mpp *.vsdx *.odt *.ods *.odp *.odm *.odc *.odb *.wps *.xlk *.ppt *.pst *.dwg *.dxf *.dxg *.wpd *.doc *.xls *.pdf *.rtf *.txt *.pub >>%APPDATA%\flip.txt
- cmd/T: /U /Q /C copy /Y "{Malware File Directory}\{Malware File Name}" "{Name of the file it will replace}.jse" && del /Q/F "{Name of the file it will replace}"
- wscript /B /E:JScript "%Application Data%\{Random Numbers}.fop"
- cscript /B /E:JScript "%Application Data%\{Random Numbers}.fop"
- rundll32 "{Random Numbers}.com" Initialize
It displays the following fake error messages:

Download Routine
This Trojan connects to the following website(s) to download and execute a malicious file:
- https://{BLOCKED}.{BLOCKED}.152.55/2/1.php
It saves the files it downloads using the following names:
- %Application Data%\{Random Numbers}.fop
- %Application Data%\{Random Numbers}.edp
- %Application Data%\{Random Numbers}.com
Information Theft
This Trojan gathers the following data:
- Computer Name
- User Name
- User Domain
Other Details
This Trojan does the following:
- The document contains the following message details luring users to enable macro content:

- If the dropped script fails to download a file from its C&C Server, it locates for files with the following extensions in shared and removable drives, deletes the file and replaces the deleted file with a copy of itself:
- .mpp
- .vsdx
- .odt
- .ods
- .odp
- .odm
- .odc
- .odb
- .wps
- .xlk
- .ppt
- .pst
- .dwg
- .dxf
- .dxg
- .wpd
- .doc
- .xls
- .pdf
- .rtf
- .txt
- .pub
However, as of this writing, the said sites are inaccessible.
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
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 3
Identify and terminate files detected as Trojan.W97M.JASCREX.BSUB
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- Windows Task Manager may not display all running processes. In this case, please use a third-party process viewer, preferably Process Explorer, to terminate the malware/grayware/spyware file. You may download the said tool here.
- If the detected file is displayed in either Windows Task Manager or Process Explorer but you cannot delete it, restart your computer in safe mode. To do this, refer to this link for the complete steps.
- If the detected file is not displayed in either Windows Task Manager or Process Explorer, continue doing the next steps.
To terminate the malware/grayware/spyware process:
- Scan your computer with your Trend Micro product and take note of the name of the malware/grayware/spyware detected.
- Open Windows Task Manager. To do this, press CTRL+SHIFT+ESC.
- View the list of all running programs. To do this:
• For Windows 7 and Server 2008 (R2) users, click the Processes tab.
• For Windows 8, 8.1, 10, and Server 2012 (R2) users, click the Details tab. - In the list of running programs, locate a malware/grayware/spyware file detected earlier.
- Select the detected files, then press either the End Task or the End Process button, depending on the version of Windows you are using.
- Do the same for the remaining detected malware/grayware/spyware files in the list of running programs.
- To check if the malware/grayware/spyware process has been terminated, close Task Manager, and then open it again.
- Close Task Manager.
Step 4
Search and delete these files
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There may be some component files that are hidden. Please make sure you check the
Search Hidden Files and Folders checkbox in the More advanced options option to include all hidden files and folders in the search result.
%System Root%\MyMusic\presskey.cmd%SystemRoot%\MyMusic\presskey.jse%Application Data%\{RandomNumbers}.fop%Application Data%\{Random Numbers}.edp%Application Data%\{Random Numbers}.comTo delete malware/grayware component files:
- Search for the following files:
- %System Root%\MyMusic\presskey.cmd
- %SystemRoot%\MyMusic\presskey.jse
- %Application Data%\{RandomNumbers}.fop
- %Application Data%\{Random Numbers}.edp
- %Application Data%\{Random Numbers}.com
Note: To do a search for the following files, right-click Start then click Search... or Find..., depending on the version of Windows you are running. For each file to be deleted, type its file name in the Named input box. In the Look In drop-down list, select My Computer, then press Enter. - Once located, select the file then press SHIFT+DELETE to permanently delete the file.
- Repeat the said steps for all files listed.
Step 5
Search and delete this folder
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Please make sure you check the
Search Hidden Files and Folders checkbox in the More advanced options option to include all hidden folders in the search result.
To delete the malware/grayware folder:
- Right-click Start then click Search... or Find..., depending on the version of Windows you are running.
- In the Named input box, type:
- In the Look In drop-down list, select My Computer, then press Enter.
- Once located, select the folder then press SHIFT+DELETE to permanently delete the folder.
Step 6
Scan your computer with your Trend Micro product to delete files detected as Trojan.W97M.JASCREX.BSUB. 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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