WORM_AMITIS.A
W32.Casail.A (Symantec); Trojan:Win32/VB.CT (Microsoft); Win32/AutoRun.VB.AR (ESET-NOD32)
Windows
Threat Type: Worm
Destructiveness: No
Encrypted:
In the wild: Yes
OVERVIEW
This worm arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.
It drops an AUTORUN.INF file to automatically execute the copies it drops when a user accesses the drives of an affected system.
TECHNICAL DETAILS
190,948 bytes
EXE
No
21 May 2014
Arrival Details
This worm 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 worm drops the following files:
- %Windows%\uha.exe
(Note: %Windows% is the Windows folder, where it usually is C:\Windows on all Windows operating system versions.)
It drops the following copies of itself into the affected system:
- %User Temp%\123897.exe
- %System%\odbcasvc.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.. %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)
It drops the following non-malicious file:
- %System%\mswinsck.ocx
- %System%\scrrun.dll
- %System%\msvbvm60.dll
(Note: %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)
Autostart Technique
This worm registers itself as a system service to ensure its automatic execution at every system startup by adding the following registry entries:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\odbcasvc
ImagePath = %System%\odbcasvc.EXE
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\odbcasvc
Description = Microsoft Data Access - ODBC Administration Service
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\odbcasvc
DisplayName = ODBC Administration Service
Propagation
This worm drops the following copy(ies) of itself in all removable drives:
- {Removable Drive Letter}:\Recycled\desktop.ini
- {Removable Drive Letter}:\Recycled\INFO.exe
It drops an AUTORUN.INF file to automatically execute the copies it drops when a user accesses the drives of an affected system.
SOLUTION
9.800
10.808.04
21 May 2014
10.809.00
22 May 2014
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
Delete this registry key
Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.
- In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services
- odbcasvc
- odbcasvc
Step 5
Search and delete this file
- %Windows%\uha.exe
- {Removable Drive Letter}:\Autorun.inf
Step 6
Restart in normal mode and scan your computer with your Trend Micro product for files detected as WORM_AMITIS.A. 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 7
Scan your computer with your Trend Micro product to delete files detected as WORM_AMITIS.A. 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.
Did this description help? Tell us how we did.