WORM_DORKBOT.CF
Windows 2000, Windows XP, Windows Server 2003
![](/vinfo/imgFiles/legend.jpg)
Threat Type: Worm
Destructiveness: No
Encrypted: Yes
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 deletes the initially executed copy of itself.
TECHNICAL DETAILS
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:
- %User Profile%\Application Data\Giwuwa.exe
(Note: %User Profile% is the current user's profile folder, which is usually C:\Windows\Profiles\{user name} on Windows 98 and ME, C:\WINNT\Profiles\{user name} on Windows NT, and C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003.)
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
Giwuwa = "%User Profile%\Application Data\Giwuwa.exe"
Propagation
This worm creates the following folders in all removable drives:
- RECYCLER
It drops the following copy(ies) of itself in all removable drives:
- {Removable Drive}:\RECYCLER\0x{random}.exe
Backdoor Routine
This worm connects to any of the following IRC server(s):
- av.{BLOCKED}en.cc
- av.{BLOCKED}nc.cz
Other Details
This worm connects to the following URL(s) to get the affected system's IP address:
- http://api.wipmania.com
It deletes the initially executed copy of itself
NOTES:
It then searches for folders in removable drives then creates an .LNK file as {folder name}.lnk that points to the malware copy. It then sets the attribute of the original folder to Read-Only, Hidden and System to trick users into thinking that they are opening the legitimate folder.
SOLUTION
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
Restart in Safe Mode
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
- Giwuwa = "%User Profile%\Application Data\Giwuwa.exe"
- Giwuwa = "%User Profile%\Application Data\Giwuwa.exe"
Step 4
Search and delete this folder
- {Removable Drive}:\RECYCLER
Step 5
Search and delete this file
- {Removable Drive}:\{folder name}.lnk
Step 6
Restart in normal mode and scan your computer with your Trend Micro product for files detected as WORM_DORKBOT.CF. 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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