WORM_DORKBOT.ABW
Worm.Win32.Ngrbot.whb (Kaspersky), Worm:Win32/Dorkbot.I (Microsoft)
Windows 2000, Windows Server 2003, Windows XP (32-bit, 64-bit), Windows Vista (32-bit, 64-bit), Windows 7 (32-bit, 64-bit)
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 modifies the Internet Explorer Zone Settings.
It deletes itself after execution.
TECHNICAL DETAILS
101,888 bytes
EXE
Yes
11 Dec 2013
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.
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
Adobe System Incorporated = "%User Temp%\Adobe\Reader_sl.exe"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
{Random Characters 1} = "%Application Data%\Identities\{Random Characters 1}.exe"
Other System Modifications
This worm adds the following registry entries:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Direct3D\MostRecentApplication
Name = "{Random Letter}.exe"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
DirectDraw\MostRecentApplication
Name = "{Random Letter}.exe"
Web Browser Home Page and Search Page Modification
This worm modifies the Internet Explorer Zone Settings.
Other Details
This worm connects to the following possibly malicious URL:
- http://{BLOCKED}.{BLOCKED}.8.53/8883.exe
- http://{BLOCKED}-traffic.pw/system.exe
It drops the following file(s)/component(s):
- %Application Data%\{Random Letter}.exe
- %Application Data%\Identities\{Random Characters 1}.exe
- %Application Data%\{Random Characters 2}
- %Application Data%\miner.exe
- %TEMP%\Adobe\Reader_sl.exe
- %TEMP%\{Random Characters 2}
(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Roaming on Windows Vista and 7.)
It deletes itself after execution.
SOLUTION
9.700
10.466.02
28 Nov 2013
10.467.00
29 Nov 2013
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
Scan your computer with your Trend Micro product and note files detected as WORM_DORKBOT.ABW
Step 3
Restart in Safe Mode
Step 4
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
- Adobe System Incorporated = "%User Temp%\Adobe\Reader_sl.exe"
- Adobe System Incorporated = "%User Temp%\Adobe\Reader_sl.exe"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
- {Random Characters 1} = "%Application Data%\Identities\{Random Characters 1}.exe"
- {Random Characters 1} = "%Application Data%\Identities\{Random Characters 1}.exe"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Direct3D\MostRecentApplication
- Name = "{Random Letter}.exe"
- Name = "{Random Letter}.exe"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\DirectDraw\MostRecentApplication
- Name = "{Random Letter}.exe"
- Name = "{Random Letter}.exe"
Step 5
Search and delete these files
- %Application Data%\{Random Letter}.exe
- %Application Data%\Identities\{Random Characters 1}.exe
- %Application Data%\{Random Characters 2}
- %Application Data%\miner.exe
- %TEMP%\Adobe\Reader_sl.exe
- %TEMP%\{Random Characters 2}
Step 6
Reset Internet security settings
Step 7
Restart in normal mode and scan your computer with your Trend Micro product for files detected as WORM_DORKBOT.ABW. 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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