WORM_COSMU.EDS

 Analysis by: Cris Nowell Pantanilla

 ALIASES:

Trojan.Win32.Cosmu.cdqg (Kaspersky), Worm:Win32/Sovfo.A (Microsoft), Trojan.Festalco (Symantec)

 PLATFORM:

Windows

 OVERALL RISK RATING:
 REPORTED INFECTION:

  • Threat Type: Worm

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Via physical/removable drives


This worm arrives via removable drives.

It connects to certain websites to send and receive information. However, as of this writing, the said sites are inaccessible.

  TECHNICAL DETAILS

File Size:

200,704 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

09 Nov 2016

Payload:

Connects to URLs/IPs

Arrival Details

This worm arrives via removable drives.

Installation

This worm drops the following copies of itself into the affected system and executes them:

  • %User Profile%\{7 random characters}.exe

(Note: %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003, or C:\Users\{user name} on Windows Vista and 7.)

Autostart Technique

This worm drops the following file(s) in the Windows User Startup folder to enable its automatic execution at every system startup:

  • %User Startup%\{7 random characters}.lnk

(Note: %User Startup% is the current user's Startup folder, which is usually C:\Documents and Settings\{user}\Start Menu\Programs\Startup on Windows 2000 and XP, and C:\Documents and Settings\{User name}\Start Menu\Programs\Startup on Windows Vista, 7, and 8.)

Propagation

This worm drops the following copy of itself in all physical and removable drives:

  • {Drive Letter}:\Hot fotos.exe
  • {Drive Letter}:\My Musik(2013).exe

Information Theft

This worm gathers the following data:

  • User
  • Machine
  • Files (on the system)
  • Computer Name
  • Date Time

Other Details

This worm connects to the following website to send and receive information:

  • http://www.{BLOCKED}ntronproject.site11.com/post.php

However, as of this writing, the said sites are inaccessible.

  SOLUTION

Minimum Scan Engine:

9.800

Step 1

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

Step 2

Identify and terminate files detected as WORM_COSMU.EDS

[ Learn More ]
  1. 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.
  2. 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.
  3. If the detected file is not displayed in either Windows Task Manager or Process Explorer, continue doing the next steps.

Step 3

Search and delete these components

[ Learn More ]
There may be some components 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.  %User Startup%\{7 random characters}.lnk

Step 4

Scan your computer with your Trend Micro product to delete files detected as WORM_COSMU.EDS. 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 this Knowledge Base page for more information.


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