JS_NEMUCOD.IA
JS/DwnLdr-MON (Sophos), JS/Donwloader.Agent (AVG), JS/Nemucod.AJ!tr.dldr (Fortinet)
Windows
Threat Type: Trojan
Destructiveness: No
Encrypted: Yes
In the wild: Yes
OVERVIEW
Via email, Downloaded from the Internet
This Trojan arrives as an attachment to email messages spammed by other malware/grayware or malicious users. It arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.
TECHNICAL DETAILS
8,334 bytes
EXE
No
02 Jul 2015
Connects to URLs/IPs, Downloads files
Arrival Details
This Trojan arrives as an attachment to email messages spammed by other malware/grayware or malicious users.
It arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.
Download Routine
This Trojan accesses the following websites to download files:
- http://{BLOCKED}lantiers.fr/document.php?rnd=7531&id=5556565E104A09011D0116240001170D031105084A070B09
- http://{BLOCKED}lantiers.fr/document.php?rnd=7082&id=5556565E104A09011D0116240001170D031105084A070B09
- http://{BLOCKED}lantiers.fr/document.php?rnd=403&id=5556565E104A09011D0116240001170D031105084A070B09
- http://{BLOCKED}t.com/document.php?rnd=7531&id=5556565E104A09011D0116240001170D031105084A070B09
- http://{BLOCKED}t.com/document.php?rnd=7082&id=5556565E104A09011D0116240001170D031105084A070B09
- http://{BLOCKED}t.com/document.php?rnd=403&id=5556565E104A09011D0116240001170D031105084A070B09
- http://{BLOCKED}a.net.br/document.php?rnd=7531&id=5556565E104A09011D0116240001170D031105084A070B09
- http://{BLOCKED}a.net.br/document.php?rnd=7082&id=5556565E104A09011D0116240001170D031105084A070B09
- http://{BLOCKED}a.net.br/document.php?rnd=403&id=5556565E104A09011D0116240001170D031105084A070B09
It saves the files it downloads using the following names:
- %User Temp%\{random numbers 1}.exe
- %User Temp%\{random numbers 2}.exe
- %User Temp%\{random numbers 3}.exe - detected as TSPY_FAREIT.RUI
(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.)
SOLUTION
9.750
11.736.06
17 Jun 2015
11.737.00
17 Jun 2015
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
Remove the malware/grayware file dropped/downloaded by JS_NEMUCOD.IA. (Note: Please skip this step if the threat(s) listed below have already been removed.)
Step 4
Search and delete these files
- %User Temp%\{random numbers 1}.exe
- %User Temp%\{random numbers 2}.exe
Step 5
Scan your computer with your Trend Micro product to delete files detected as JS_NEMUCOD.IA. 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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