TSPY_ZBOT.USR
W32/Zbot.DHN!tr (Fortinet), PWS:Win32/Zbot.gen!AL (Microsoft), Win32/Spy.Zbot.AAU trojan (NOD32)
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: Yes
In the wild: Yes
OVERVIEW
This spyware may be downloaded from remote sites by other malware.
It is injected into all running processes to remain memory resident.
It attempts to access certain websites. However, the websites are inaccessible as of this writing. It deletes itself after execution.
TECHNICAL DETAILS
Arrival Details
This spyware may be downloaded from remote site(s) by the following malware:
- TSPY_FAREIT.JBB
Installation
This spyware drops the following copies of itself into the affected system and executes them:
- %Application Data%\{random folder}\{random}.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%\Microsoft\Address Book\{username}.wab
- %User Temp%\tmp{random values}.bat - Deletes the initial executed copy of malware and itself
(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.. %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Local\Temp on Windows Vista and 7.)
It creates the following folders:
- %Application Data%\{random folder}
- %Application Data%\Microsoft\Address Book
(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 is injected into all running processes to remain memory resident.
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} = "%Application Data%\{random folder}\{random}.exe"
Other System Modifications
This spyware adds the following registry keys:
HKEY_CURRENT_USER\Software\Microsoft\
{random}
HKEY_CURRENT_USER\Software\Microsoft\
WAB
It adds the following registry entries:
HKEY_CURRENT_USER\Software\Microsoft\
WAB\WAB4\Wab File Name
(Default) = "%Application Data%\Microsoft\Address Book\{username}.wab"
HKEY_CURRENT_USER\Software\Microsoft\
{random}
{random 1} = "{random characters}"
HKEY_CURRENT_USER\Software\Microsoft\
{random}
{random 2} = "{random characters}"
HKEY_CURRENT_USER\Software\Microsoft\
{random}
{random 3} = "{random characters}"
HKEY_CURRENT_USER\Software\Microsoft\
{random}
{random 4} = "{random characters}"
HKEY_CURRENT_USER\Software\Microsoft\
{random}
{random 5} = "{random characters}"
HKEY_CURRENT_USER\Software\Microsoft\
{random}
{random 6} = "{random characters}"
HKEY_CURRENT_USER\Software\Microsoft\
{random}
{random 7} = "{random characters}"
HKEY_CURRENT_USER\Software\Microsoft\
{random}
{random 8} = "{random characters}"
HKEY_CURRENT_USER\Software\Microsoft\
{random}
{random 9} = "{random characters}"
It creates the following registry entry(ies) to bypass Windows Firewall:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\GloballyOpenPorts\
List
28577:TCP = "28577:TCP:Enabled:TCP 28577"
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
17328:UDP = "17328:UDP:Enabled:UDP 17328"
Information Theft
This spyware accesses the following site to download its configuration file:
- {BLOCKED}.{BLOCKED}.226.107
- {BLOCKED}.{BLOCKED}.41.188
- {BLOCKED}.{BLOCKED}.110.7
- {BLOCKED}.{BLOCKED}.120.64
- {BLOCKED}.{BLOCKED}.60.178
- {BLOCKED}.{BLOCKED}.127.98
- {BLOCKED}.{BLOCKED}.105.169
- {BLOCKED}.{BLOCKED}.147.191
- {BLOCKED}.{BLOCKED}.65.223
- {BLOCKED}.{BLOCKED}.174.163
- {BLOCKED}.{BLOCKED}.125.105
- {BLOCKED}.{BLOCKED}.237.35
- {BLOCKED}.{BLOCKED}.220.237
- {BLOCKED}.{BLOCKED}.64.46
- {BLOCKED}.{BLOCKED}.160.200
Stolen Information
This spyware sends the gathered information via HTTP POST to the following URL:
- {BLOCKED}.{BLOCKED}.226.107
- {BLOCKED}.{BLOCKED}.41.188
- {BLOCKED}.{BLOCKED}.110.7
- {BLOCKED}.{BLOCKED}.120.64
- {BLOCKED}.{BLOCKED}.60.178
- {BLOCKED}.{BLOCKED}.127.98
- {BLOCKED}.{BLOCKED}.105.169
- {BLOCKED}.{BLOCKED}.147.191
- {BLOCKED}.{BLOCKED}.65.223
- {BLOCKED}.{BLOCKED}.174.163
- {BLOCKED}.{BLOCKED}.125.105
- {BLOCKED}.{BLOCKED}.237.35
- {BLOCKED}.{BLOCKED}.220.237
- {BLOCKED}.{BLOCKED}.64.46
- {BLOCKED}.{BLOCKED}.160.200
Other Details
This spyware attempts to access certain websites. However, the websites are inaccessible as of this writing.
It connects to the following URL(s) to check for an Internet connection:
- www.google.com
- www.google.com.{local country code}
It deletes itself after execution.
NOTES:
The configuration file may contain URLs where it downloads an updated copy of itself and where it sends its gathered information. It may also contain URLs of its target online banking and finance-related sites from where it steals the information. Note that the contents of the file, hence the list of websites to monitor, may change any time.
It may also gather the following information from the affected system:
- Data on cookie files (URLs)
- Email-related information such as account names, email addresses, passwords, server data, and server port
- Email information stored in the user’s Windows Address Book (WAB) file
SOLUTION
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
Remove the malware/grayware file that dropped/downloaded TSPY_ZBOT.USR
- TSPY_FAREIT.JBB
Step 3
Restart in Safe Mode
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.
- In HKEY_CURRENT_USER\Software\Microsoft
- {random}
- {random}
- In HKEY_CURRENT_USER\Software\Microsoft
- WAB
- WAB
Step 5
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
- {GUID} = "%Application Data%\{random folder}\{random}.exe"
- {GUID} = "%Application Data%\{random folder}\{random}.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"
- In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\GloballyOpenPorts\List
- 17328:UDP = "17328:UDP:Enabled:UDP 17328"
- 17328:UDP = "17328:UDP:Enabled:UDP 17328"
- In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\GloballyOpenPorts\List
- 28577:TCP = "28577:TCP:Enabled:TCP 28577"
- 28577:TCP = "28577:TCP:Enabled:TCP 28577"
Step 6
Search and delete these folders
- %Application Data%\{random folder}
- %Application Data%\Microsoft\Address Book
Step 7
Search and delete this file
- Aplication Data%\Microsoft\Address Book\{username}.wab
- %User Temp%\tmp{random values}.bat - Deletes the initial executed copy of malware
Step 8
Restart in normal mode and scan your computer with your Trend Micro product for files detected as TSPY_ZBOT.USR. 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.
NOTES:
The created registry key HKEY_CURRENT_USER\Software\Microsoft\{random} 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 if the users have one. Note that the key need not to be deleted since it won't cause the user system any harm.
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