WORM_RIMECUD.BW
Trojan:Win32/Lethic.C (Microsoft), W32/Palevo (McAfee)
Windows 2000, Windows XP, Windows Server 2003
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.
TECHNICAL DETAILS
1,433,600 bytes
EXE
Yes
06 Jan 2011
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 copies of itself into the affected system:
- %System Root%\RECYCLER\{random SID}\recyclebin.exe
(Note: %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.)
It drops the following files:
- %System Root%\RECYCLER\{random SID}\Desktop.ini
(Note: %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.)
Autostart Technique
This worm adds the following registry entries to enable its automatic execution at every system startup:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
CurrentVersion = "%System Root%\RECYCLER\{random SID}\recyclebin.exe"
HKEY_CURRENT_USER\Software\Microsoft\
Windows NT\CurrentVersion\Winlogon
Shell = "explorer.exe,%System Root%\RECYCLER\{random SID}\recyclebin.exe"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Winlogon
Taskman = "%System Root%\RECYCLER\{random SID}\recyclebin.exe"
Other System Modifications
This worm adds the following registry keys:
HKEY_CLASSES_ROOT\CLSID\{5A8A1D95-22E9-3963-2E06-90BDD094E562}
HKEY_CURRENT_USER\Software\Licenses
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
RFC1156Agent
It adds the following registry entries:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
RFC1156Agent\CurrentVersion\Parameters
TrapPollTimeMilliSecs = "3a98"
SOLUTION
9.200
7.750.03
06 Jan 2011
7.751.00
07 Jan 2011
Step 1
For Windows XP and Windows Server 2003 users, before doing any scans, please make sure you disable System Restore to allow full scanning of your computer.
Step 2
Identify and delete files detected as WORM_RIMECUD.BW using either the Startup Disk or Recovery Console
Step 3
Delete this registry value
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_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
- CurrentVersion = "%System Root%\RECYCLER\{random SID}\recyclebin.exe"
- CurrentVersion = "%System Root%\RECYCLER\{random SID}\recyclebin.exe"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows NT\CurrentVersion\Winlogon
- Shell = "explorer.exe,%System Root%\RECYCLER\{random SID}\recyclebin.exe"
- Shell = "explorer.exe,%System Root%\RECYCLER\{random SID}\recyclebin.exe"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon
- Taskman = "%System Root%\RECYCLER\{random SID}\recyclebin.exe"
- Taskman = "%System Root%\RECYCLER\{random SID}\recyclebin.exe"
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. Before you could do this, you must restart in Safe Mode. For instructions on how to do this, you may refer to this page If the preceding step requires you to restart in safe mode, you may proceed to edit the system registry.
- In HKEY_CLASSES_ROOT\CLSID
- {5A8A1D95-22E9-3963-2E06-90BDD094E562}
- {5A8A1D95-22E9-3963-2E06-90BDD094E562}
- In HKEY_CURRENT_USER\Software
- Licenses
- Licenses
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft
- RFC1156Agent
- RFC1156Agent
Step 5
Search and delete this file
- %System Root%\RECYCLER\{random SID}\Desktop.ini
Step 6
Scan your computer with your Trend Micro product to delete files detected as WORM_RIMECUD.BW. 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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