JS_LOCKY.SMDA3
JS/Nemucod.kz (McAfee); Trojan-Downloader.JS.Nemucod (Ikarus); JS/Nemucod.BOT!tr.dldr (Fortinet); JS/TrojanDownloader.Nemucod.BOW (ESET-NOD32)
Windows
Threat Type: Trojan
Destructiveness: No
Encrypted:
In the wild: Yes
OVERVIEW
This Trojan arrives as an attachment to email messages spammed by other malware/grayware or malicious users.
It executes the downloaded files. As a result, malicious routines of the downloaded files are exhibited on the affected system.
However, as of this writing, the said sites are inaccessible. It deletes itself after execution.
TECHNICAL DETAILS
Arrival Details
This Trojan arrives as an attachment to email messages spammed by other malware/grayware or malicious users.
Download Routine
This Trojan saves the files it downloads using the following names:
- %User Profile%\Local Settings\Temprad{random}.tmp -> for Windows XP
- %AppDataLocal%\Temprad{random}.tmp -> for Windows Vista and above
(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.. %AppDataLocal% is the Application Data folder found in Local Settings, where it is usually C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local 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 then executes the downloaded files. As a result, malicious routines of the downloaded files are exhibited on the affected system.
Other Details
This Trojan connects to the following possibly malicious URL:
- http://www.{BLOCKED}siveew.top/log.php?f=2.dat
However, as of this writing, the said sites are inaccessible.
It deletes itself after execution.
SOLUTION
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
Search and delete these files
- %User Profile%\Local Settings\Temprad{random}.tmp -> for Windows XP
- %AppDataLocal%\Temprad{random}.tmp -> for Windows Vista and above
Step 4
Scan your computer with your Trend Micro product to delete files detected as JS_LOCKY.SMDA3. 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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