TSPY_DYZAP.F
PWS:Win32/Dyzap.F (Microsoft); Trojan.Win32.Staser.atcy (Kaspersky)
Windows
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.
TECHNICAL DETAILS
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:
- %AppDataLocal%\f5e83w4ef.dat
- %System%\config\systemprofile\Application Data\f5e83w4ef.dat
(Note: %AppDataLocal% is the Application Data folder found in Local Settings, where it is usually C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local 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.. %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)
It drops the following copies of itself into the affected system:
- %AppDataLocal%\{random letters}.exe
- %Windows%\{random letters}.exe
(Note: %AppDataLocal% is the Application Data folder found in Local Settings, where it is usually C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local 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.. %Windows% is the Windows folder, where it usually is C:\Windows on all Windows operating system versions.)
Autostart Technique
This spyware registers itself as a system service to ensure its automatic execution at every system startup by adding the following registry entries:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\googleupdate
ImagePath = "%Windows%\{random letters}.exe"
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\googleupdate
DisplayName = "Google Update Service"
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\googleupdate
Start = "2"
It adds the following registry entries to enable its automatic execution at every system startup:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
(Default) = "%AppDataLocal%\{random letters}.exe"
It registers as a system service to ensure its automatic execution at every system startup by adding the following registry keys:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\googleupdate
Other Details
This spyware connects to the following possibly malicious URL:
- http://{BLOCKED}.{BLOCKED}3.102.211:443
- http://{BLOCKED}.{BLOCKED}3.102.211:4443
- http://{BLOCKED}.{BLOCKED}03.50.17:443
- http://{BLOCKED}.{BLOCKED}03.50.17:4443
- http://{BLOCKED}.{BLOCKED}03.50.69:443
- http://{BLOCKED}.{BLOCKED}03.50.69:4443
- http://{BLOCKED}.{BLOCKED}03.50.71:443
- http://{BLOCKED}.{BLOCKED}03.50.71:4443
- http://{BLOCKED}.{BLOCKED}3.8.68:443
- http://{BLOCKED}.{BLOCKED}3.8.68:4443
- http://{BLOCKED}.{BLOCKED}5.99.136:443
- http://{BLOCKED}.{BLOCKED}5.99.136:4443
- http://{BLOCKED}.{BLOCKED}.196.90:443
- http://{BLOCKED}.{BLOCKED}.196.90:4443
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
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
- (Default) = "%AppDataLocal%\{random letters}.exe"
- (Default) = "%AppDataLocal%\{random letters}.exe"
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_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services
- googleupdate
- googleupdate
Step 6
Search and delete this file
- %AppDataLocal%\f5e83w4ef.dat
- %System%\config\systemprofile\Application Data\f5e83w4ef.dat
Step 7
Restart in normal mode and scan your computer with your Trend Micro product for files detected as TSPY_DYZAP.F. 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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