TSPY_ZBOT.KVB
PWS:Win32/Zbot.gen!AF (Microsoft), PWS-Zbot.gen.alu (McAfee), a variant of Win32/Kryptik.AMKI trojan (Eset)
Windows 2000, Windows XP, Windows Server 2003
Threat Type: Spyware
Destructiveness: No
Encrypted:
In the wild: Yes
OVERVIEW
This spyware arrives as an attachment to email messages spammed by other malware/grayware or malicious users. It 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.
It deletes the initially executed copy of itself.
TECHNICAL DETAILS
Arrival Details
This spyware arrives as an attachment to email messages spammed by other malware/grayware or malicious users.
It 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:
- %User Profile%\Application Data\{random folder name}\{random file name}.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.)
It drops the following files:
- %User Profile%\Application Data\Microsoft\Address Book\{User Name}.wab
(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.)
It creates the following folders:
- %User Profile%\Application Data\{random folder name}
- %User Profile%\Application Data\Microsoft\Address Book
(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 spyware adds the following registry entries to enable its automatic execution at every system startup:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
{GUID} = "%User Profile%\Application Data\{random folder name}\{random file name}.exe"
Other System Modifications
This spyware adds the following registry keys:
HKEY_CURRENT_USER\Software\Microsoft\
{random}
HKEY_CURRENT_USER\Software\Microsoft\
WAB
HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Privacy
It adds the following registry entries:
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"
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\GloballyOpenPorts\
List
{port}:TCP = "{port}:TCP:Enabled:TCP {port}"
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\GloballyOpenPorts\
List
{port}:UDP = "{port}:UDP:Enabled:UDP {port}"
Web Browser Home Page and Search Page Modification
This spyware modifies Internet Explorer zone settings.
Other Details
This spyware connects to the following URL(s) to check for an Internet connection:
- http://www.bing.com/
- http://www.google.com/
It connects to the following possibly malicious URL:
- {BLOCKED}.{BLOCKED}.161.33
- {BLOCKED}.{BLOCKED}.136.13
- {BLOCKED}.{BLOCKED}.182.46
- {BLOCKED}.{BLOCKED}.150.198
- {BLOCKED}.{BLOCKED}.128.151
- {BLOCKED}.{BLOCKED}.125.228
- {BLOCKED}.{BLOCKED}.1.196
- {BLOCKED}.{BLOCKED}.172.166
- {BLOCKED}.{BLOCKED}.0.39
- {BLOCKED}.{BLOCKED}.128.106
- {BLOCKED}.{BLOCKED}.128.94
- {BLOCKED}.{BLOCKED}.94.249
- {BLOCKED}.{BLOCKED}.12.153
- {BLOCKED}.{BLOCKED}.145.68
It deletes the initially executed copy of itself