TSPY_ZBOT.UCH
PWS:Win32/Zbot(Microsoft), Win32/Spy.Zbot.AAO trojan(Ese)
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: Spyware
Destructiveness: No
Encrypted:
In the wild: Yes
OVERVIEW
This spyware 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 Internet Explorer security settings. This puts the affected computer at greater risk, as it allows malicious URLs to be accessed by the computer.
TECHNICAL DETAILS
368,853 bytes
EXE
Yes
04 Sep 2013
Arrival Details
This spyware 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 spyware drops the following copies of itself into the affected system and executes them:
- %Application Data%\{random folder 1}\{random file name}.exe
(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 drops the following files:
- %Application Data%\{random folder 2}\{random file name}.{random extension}
- %Application Data%\{random folder 3}\{random file name}.{random extension}
- %Application Data%\Microsoft\Address Book\{user name}.wab
- %Application Data%\Microsoft\Address Book\{user name}.wab~
(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 creates the following folders:
- %Application Data%\{random folder 1}
- %Application Data%\{random folder 2}
- %Application Data%\{random folder 3}
(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.)
Autostart Technique
This spyware adds the following registry entries to enable its automatic execution at every system startup:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
{random} = "%Application Data%\{random folder 1}\{random file name}.exe"
Other System Modifications
This spyware adds the following registry keys:
HKEY_CLASSES_ROOT\.s
HKEY_CLASSES_ROOT\.s\ShellNew
HKEY_CLASSES_ROOT\S9.Document
HKEY_CLASSES_ROOT\S9.Document\DefaultIcon
HKEY_CLASSES_ROOT\S9.Document\shell
HKEY_CLASSES_ROOT\S9.Document\shell\
open
HKEY_CLASSES_ROOT\S9.Document\shell\
open\command
HKEY_CLASSES_ROOT\S9.Document\shell\
print
HKEY_CLASSES_ROOT\S9.Document\shell\
print\command
HKEY_CLASSES_ROOT\S9.Document\shell\
printto
HKEY_CLASSES_ROOT\S9.Document\shell\
printto\command
HKEY_CURRENT_USER\Software\Local AppWizard-Generated Applications
HKEY_CURRENT_USER\Software\Local AppWizard-Generated Applications\
S9
HKEY_CURRENT_USER\Software\Local AppWizard-Generated Applications\
S9\Recent File List
HKEY_CURRENT_USER\Software\Local AppWizard-Generated Applications\
S9\Settings
HKEY_CURRENT_USER\Software\Microsoft\
{random}
HKEY_CURRENT_USER\Software\Microsoft\
WAB
HKEY_CURRENT_USER\Software\Microsoft\
WAB\WAB4
HKEY_CURRENT_USER\Software\Microsoft\
WAB\WAB4\Wab File Name
HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Privacy
It adds the following registry entries:
HKEY_CLASSES_ROOT\.s
(Default) = "S9.Document"
HKEY_CLASSES_ROOT\.s\ShellNew
NullFile = ""
HKEY_CLASSES_ROOT\S9.Document
(Default) = "S9.Document"
HKEY_CLASSES_ROOT\S9.Document\DefaultIcon
(Default) = "%Application Data%\{random folder 1}\{random file name}.exe,0"
HKEY_CLASSES_ROOT\S9.Document\shell\
open\command
(Default) = "%Application Data%\{random folder 1}\{random file name}.exe "%1""
HKEY_CLASSES_ROOT\S9.Document\shell\
print\command
(Default) = "%Application Data%\{random folder 1}\{random file name}.exe /p "%1""
HKEY_CLASSES_ROOT\S9.Document\shell\
printto\command
(Default) = "%Application Data%\{random folder 1}\{random file name}.exe /pt "%1" "%2" "%3" "%4""
HKEY_CURRENT_USER\Software\Microsoft\
{random}
{random key 1} = "{random value}"
HKEY_CURRENT_USER\Software\Microsoft\
{random}
{random key 2} = "{random value}"
HKEY_CURRENT_USER\Software\Microsoft\
WAB\WAB4
OlkContactRefresh = "0"
HKEY_CURRENT_USER\Software\Microsoft\
WAB\WAB4
OlkFolderRefresh = "0"
HKEY_CURRENT_USER\Software\Microsoft\
WAB\WAB4
FirstRun = "1"
HKEY_CURRENT_USER\Software\Microsoft\
WAB\WAB4\Wab File Name
(Default) = "%Application Data%\Microsoft\Address Book\{user name}.wab"
HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Privacy
CleanCookies = "0"
It creates the following registry entry(ies) to bypass Windows Firewall:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\AuthorizedApplications\
List
%Windows%\explorer.exe = "%Windows%\explorer.exe:*:Enabled:Windows Explorer"
Web Browser Home Page and Search Page Modification
This spyware modifies Internet Explorer zone settings.
Other Details
This spyware attempts to access the following websites to download files, which are possibly malicious:
- http://{BLOCKED}.{BLOCKED}.55.32/~frandric/.cpanel/cgi-bin/.home/pan/f.bin
- http://{BLOCKED}e-citadelhost/folder/file.php
- http://{BLOCKED}.{BLOCKED}.55.32/~frandric/.cpanel/cgi-bin/.home/pan/g.php
- http://{BLOCKED}e-host1/folder/file.php
NOTES:
This spware modifies its file attributes to Hidden after execution.
SOLUTION
9.300
10.264.01
07 Sep 2013
10.265.00
08 Sep 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
Restart in Safe Mode
Step 3
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_CLASSES_ROOT
- .s
- .s
- In HKEY_CLASSES_ROOT
- S9.Document
- S9.Document
- In HKEY_CURRENT_USER\Software
- Local AppWizard-Generated Applications
- Local AppWizard-Generated Applications
- In HKEY_CURRENT_USER\Software\Microsoft
- WAB
- WAB
- In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer
- Privacy
- Privacy
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
- {random} = "%Application Data%\{random folder 1}\{random file name}.exe"
- {random} = "%Application Data%\{random folder 1}\{random file name}.exe"
- In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\AuthorizedApplications\List
- %Windows%\explorer.exe = "%Windows%\explorer.exe:*:Enabled:Windows Explorer"
- %Windows%\explorer.exe = "%Windows%\explorer.exe:*:Enabled:Windows Explorer"
Step 5
Search and delete these folders
- %Application Data%\{random folder 1}
- %Application Data%\{random folder 2}
- %Application Data%\{random folder 3}
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 TSPY_ZBOT.UCH. 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 8
The following created registry key(s) cannot be identified by the user since there are no reference values in the created key. The only way it can be identified is by comparing the present keys with a backup of the system registry. Note that the said key(s) do not have to be deleted since it won't be harmful to the system:
- HKEY_CURRENT_USER\Software\Microsoft\{random}
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