TROJ_SHELLDOWN.H
Windows
Threat Type: Trojan
Destructiveness: No
Encrypted:
In the wild: Yes
OVERVIEW
Dropped by other malware, Downloaded from the Internet
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 does not have any propagation routine.
It does not have any backdoor routine.
It connects to certain websites to send and receive information. However, as of this writing, the said sites are inaccessible. It gathers information and reports it to its servers.
TECHNICAL DETAILS
98,304 bytes
EXE
No
18 Sep 2017
Connects to URLs/IPs, Steals information
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 the following copies of itself into the affected system and executes them:
- %User Temp%\mshta.exe
(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)
It drops and executes the following files:
- %User Temp%\{malware filename}.doc - decoy document
(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)
It adds the following mutexes to ensure that only one of its copies runs at any one time:
- /jquery.php
Propagation
This Trojan does not have any propagation routine.
Backdoor Routine
This Trojan does not have any backdoor routine.
Other Details
This Trojan connects to the following website to send and receive information:
- https://{BLOCKED}c.au-syd.{BLOCKED}mix.net/jquery.php?docs={encrypted, contains hostname}&faid={random numbers}
It does the following:
- This malware uses a Word icon to disguise itself as a Word document.
- It connects to its C&C server to receive arbitrary codes and commands which it executes.
However, as of this writing, the said sites are inaccessible.
It gathers the following information and reports it to its servers:
- Host name
SOLUTION
9.850
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
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
Restart in Safe Mode
Step 4
Search and delete this file
- %User Temp%\{malware filename}.doc
- %User Temp%\mshta.exe
Step 5
Restart in normal mode and scan your computer with your Trend Micro product for files detected as TROJ_SHELLDOWN.H. 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.
Step 6
Scan your computer with your Trend Micro product to delete files detected as TROJ_SHELLDOWN.H. 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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