TSPY_ZBOT.YUYAID
Trojan-Spy.Win32.Zbot.vpwy (Kaspersky); PWS:Win32/Zbot!rfn (Microsoft);
Windows
Threat Type: Spyware
Destructiveness: No
Encrypted:
In the wild: Yes
OVERVIEW
Downloaded from the Internet
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 does not have any propagation routine.
It does not have any backdoor routine.
It modifies the Internet Explorer Zone Settings.
As of this writing, the said sites are inaccessible.
It steals certain information from the system and/or the user.
It deletes the initially executed copy of itself.
TECHNICAL DETAILS
263,168 bytes
EXE
Yes
10 Oct 2015
Connects to URLs/IPs, Downloads files
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%\Hoim\wiam.exe - detected as TSPY_ZBOT.YUYAID
(Note: %Application Data% is the Application Data folder, where it usually is C:\Documents and Settings\{user name}\Application Data on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Roaming on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)
It drops the following non-malicious files:
- %Application Data%\Uhba\ahemo.lap
- %Application Data%\Uhba\ahemo.tmp
(Note: %Application Data% is the Application Data folder, where it usually is C:\Documents and Settings\{user name}\Application Data on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Roaming on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)
It creates the following folders:
- %Application Data%\Hoim
- %Application Data%\Uhba
(Note: %Application Data% is the Application Data folder, where it usually is C:\Documents and Settings\{user name}\Application Data on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Roaming on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)
It adds the following mutexes to ensure that only one of its copies runs at any one time:
- Local\{GUID}
- Global\{GUID}
It injects codes into the following process(es):
- explorer.exe
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%\Hoim\wiam.exe"
Other System Modifications
This spyware adds the following registry keys:
HKEY_CURRENT_USER\Software\Microsoft\
Etuhi
It adds the following registry entries:
HKEY_CURRENT_USER\Software\Microsoft\
Etuhi
Guxyugtu = "{random values}"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\AuthorizedApplications\
List
%Windows%\explorer.exe = "%Windows%\explorer.exe:*:Enabled:Windows Explorer"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\AuthorizedApplications\
List
%System%\explorer.exe = "%System%\system32\explorer.exe:*:Enabled:Windows Explorer"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings
WarnonBadCertRecving = "0"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings
EnableSPDY3_0 = "0"
Propagation
This spyware does not have any propagation routine.
Backdoor Routine
This spyware does not have any backdoor routine.
Web Browser Home Page and Search Page Modification
This spyware modifies the Internet Explorer Zone Settings.
Download Routine
This spyware connects to the following URL(s) to download its configuration file:
- http://{BLOCKED}s.ru/tsuchiya.jpg
As of this writing, the said sites are inaccessible.
Information Theft
This spyware steals the following information:
- 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
- Online banking credentials
- Personal digital certificate
Other Details
This spyware deletes the initially executed copy of itself
The configuration file may contain URLs that it access to download an updated copy of itself and to send its gathered information.
SOLUTION
9.750
11.904.04
07 Sep 2015
11.905.00
08 Sep 2015
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
Note that not all files, folders, and registry keys and entries are installed on your computer during this malware's/spyware's/grayware's execution. This may be due to incomplete installation or other operating system conditions. If you do not find the same files/folders/registry information, please proceed to the next step.
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} = "%Application Data%\Hoim\wiam.exe"
- {GUID} = "%Application Data%\Hoim\wiam.exe"
- In HKEY_CURRENT_USER\Software\Microsoft\Etuhi
- Guxyugtu = "{random values}"
- Guxyugtu = "{random values}"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\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\ControlSet001\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\AuthorizedApplications\List
- %System%\explorer.exe = "%System%\system32\explorer.exe:*:Enabled:Windows Explorer"
- %System%\explorer.exe = "%System%\system32\explorer.exe:*:Enabled:Windows Explorer"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings
- WarnonBadCertRecving = "0"
- WarnonBadCertRecving = "0"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings
- EnableSPDY3_0 = "0"
- EnableSPDY3_0 = "0"
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
- Etuhi
- Etuhi
Step 6
Search and delete these files
- %Application Data%\Uhba\ahemo.lap
- %Application Data%\Uhba\ahemo.tmp
Step 7
Search and delete these folders
- %Application Data%\Hoim
- %Application Data%\Uhba
Step 8
Reset Internet security settings
Step 9
Restart in normal mode and scan your computer with your Trend Micro product for files detected as TSPY_ZBOT.YUYAID. 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 10
Scan your computer with your Trend Micro product to delete files detected as TSPY_ZBOT.YUYAID. 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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