TSPY_ZBOT.HYU
PWS:Win32/Zbot (Microsoft), Trojan-PWS.Win32.Zbot (Ikarus), PWS-Zbot-FAQD!5AE727B75A5F (NAI)
Windows 2000, Windows XP, Windows Server 2003
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 the Internet Explorer Zone Settings.
It deletes itself after execution.
TECHNICAL DETAILS
161,414 bytes
EXE
Yes
24 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 files:
- %User Profile%\Application Data\{random folder name 2}\{random file name}
(Note: %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003, or C:\Users\{user name} on Windows Vista and 7.)
It drops the following copies of itself into the affected system:
- %User Profile%\Application Data\{random folder name 1}\{random file name}.exe
(Note: %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003, or C:\Users\{user name} on Windows Vista and 7.)
It creates the following folders:
- %User Profile%\Application Data\{random folder name 1}
- %User Profile%\Application Data\{random folder name 2}
(Note: %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003, or C:\Users\{user name} 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
{GUID} = "%User Profile%\Application Data\{random folder name 1}\{random file name}.exe"
Other System Modifications
This spyware adds the following registry keys:
HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer
Privacy =
HKEY_CURRENT_USER\Software\Microsoft
{random} =
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"
Web Browser Home Page and Search Page Modification
This spyware modifies the Internet Explorer Zone Settings.
Other Details
This spyware connects to the following possibly malicious URL:
- http://{BLOCKED}e.su/newday.php
- http://{BLOCKED}e.su/speedtest.php
- http://{BLOCKED}e.su/friday.php
- http://{BLOCKED}ip.com/speedtest.php
It deletes itself after execution.
SOLUTION
9.300
10.298.03
19 Sep 2013
10.299.00
20 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
Scan your computer with your Trend Micro product and note files detected as TSPY_ZBOT.HYU
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
- {GUID} = "%User Profile%\Application Data\{random folder name 1}\{random file name}.exe"
- {GUID} = "%User Profile%\Application Data\{random folder name 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
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\Internet Explorer
- Privacy = ""
- Privacy = ""
Step 6
Search and delete these folders
- %User Profile%\Application Data\{random folder name 1}
- %User Profile%\Application Data\{random folder name 2}
Step 7
Restart in normal mode and scan your computer with your Trend Micro product for files detected as TSPY_ZBOT.HYU. 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:
Solution Note:
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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