TROJ_SMALL.SMDA
Trojan:Win32/Chiviper.C (Microsoft); Adware.StartPage (Symantec); Trojan-Downloader.Win32.Agent.cmvu (Kaspersky); Trojan.Win32.Generic!BT (Sunbelt); Trojan.Generic.7344242 (FSecure)
Windows 2000, Windows XP, Windows Server 2003
Threat Type: Trojan
Destructiveness: No
Encrypted:
In the wild: Yes
OVERVIEW
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.
TECHNICAL DETAILS
5,208 bytes
EXE
Yes
05 Apr 2012
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:
- %Windows%\Tasks\conime.exe
(Note: %Windows% is the Windows folder, which is usually C:\Windows.)
Autostart Technique
This Trojan modifies the following registry entries to ensure it automatic execution at every system startup:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Winlogon
Userinit = "%System%\userinit.exe,%Windows%\Tasks\conime.exe"
(Note: The default value data of the said registry entry is %Windows%\system32\userinit.exe,.)
Other System Modifications
This Trojan deletes the following files:
- %Windows%\Tasks\conime.exe
- %System Root%\boot
- %System Root%\359679~1.AQQ
- %System Root%\AFC9FE~1.BAT
(Note: %Windows% is the Windows folder, which is usually C:\Windows.. %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.)
Dropping Routine
This Trojan drops the following files:
- afc9fe2f418b00a0.bat
Other Details
This Trojan connects to the following possibly malicious URL:
- http://www.{BLOCKED}u.com/?{random characters}
- http://1.{BLOCKED}a.com:56/xz.txt
This report is generated via an automated analysis system.
SOLUTION
9.200
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 delete files detected as TROJ_SMALL.SMDA using either the Startup Disk or Recovery Console
Step 3
Restore these modified registry values
Important:Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this only if you know how to or you can seek your system administrator's help. You may also check out this Microsoft article first before modifying your computer's registry.
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon
- From: Userinit = "%System%\userinit.exe,%Windows%\Tasks\conime.exe"
To: Userinit = ""%Windows%\system32\userinit.exe,""
- From: Userinit = "%System%\userinit.exe,%Windows%\Tasks\conime.exe"
Step 4
Search and delete this file
- afc9fe2f418b00a0.bat
Step 5
Scan your computer with your Trend Micro product to delete files detected as TROJ_SMALL.SMDA. 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
Restore this file from backup only Microsoft-related files will be restored. If this malware/grayware also deleted files related to programs that are not from Microsoft, please reinstall those programs on you computer again.
- %Windows%\Tasks\conime.exe
- %System Root%\boot
- %System Root%\359679~1.AQQ
- %System Root%\AFC9FE~1.BAT
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