BKDR_VAWTRAK.YZY
Trojan-PSW.Win32.Tepfer.uajc (Kaspersky), Backdoor:Win32/Vawtrak (Microsoft), Win32/PSW.Papras.DC 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)
![](/vinfo/imgFiles/legend.jpg)
Threat Type: Backdoor
Destructiveness: No
Encrypted: Yes
In the wild: Yes
OVERVIEW
Downloaded from the Internet, Dropped by other malware
This backdoor arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.
It is injected into all running processes to remain memory resident.
It executes commands from a remote malicious user, effectively compromising the affected system.
TECHNICAL DETAILS
213,904 bytes
DLL
Yes
24 Jun 2014
Steals information, Compromises system security
Arrival Details
This backdoor 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 backdoor is injected into all running processes to remain memory resident.
Autostart Technique
This backdoor adds the following registry entries to enable its automatic execution at every system startup:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
{malware filename} = "regsvr32.exe /s "{malware path}\{malware filename}.dll""
Other System Modifications
This backdoor adds the following registry keys:
ADDED REGISTRY HKEY_CURRENT_USER\Software\AppDataLow
HKEY_CURRENT_USER\Software\AppDataLow\
{random key 1}
HKEY_CURRENT_USER\Software\AppDataLow\
{random key 2}
It adds the following registry entries:
HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Main
NoProtectedModebanner = "1"
HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Main
TabProcGrowth = "0"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings\
Zones\3
2500 = "3"
Backdoor Routine
This backdoor executes the following commands from a remote malicious user:
- Keylog
- Capture screenshots
- Start process (iexplore.exe, firefox.exe, outlook.exe, explorer.exe, cmd.exe, taskmgr.exe)
- Inject to process
- Perform remote shell
- Update Itself
- List processes
- Download and execute files
It connects to the following URL(s) to send and receive commands from a remote malicious user:
- http://{BLOCKED}.{BLOCKED}.233.38/posting.php?mode=reply&f=11&t=1390285619&sid={random digit}
- http://{BLOCKED}.{BLOCKED}.233.38/viewforum.php?f=11&sid={random digit}
- http://{BLOCKED}.{BLOCKED}.233.80/posting.php?mode=reply&f=11&t=1390285619&sid={random digit}
- http://{BLOCKED}.{BLOCKED}.233.80/viewforum.php?f=11&sid={random digit}
- http://{BLOCKED}.{BLOCKED}.192.106/posting.php?mode=reply&f=11&t=1390285619&sid={random digit}
- http://{BLOCKED}.{BLOCKED}.192.106/viewforum.php?f=11&sid={random digit}
- http://{BLOCKED}.{BLOCKED}.192.110/posting.php?mode=reply&f=11&t=1390285619&sid={random digit}
- http://{BLOCKED}.{BLOCKED}.192.110/viewforum.php?f=11&sid={random digit}
- http://{BLOCKED}.{BLOCKED}.51.216/posting.php?mode=reply&f=11&t=1390285619&sid={random digit}
- http://{BLOCKED}.{BLOCKED}.51.216/viewforum.php?f=11&sid={random digit}
- http://{BLOCKED}.{BLOCKED}.184.239/posting.php?mode=reply&f=11&t=1390285619&sid={random digit}
- http://{BLOCKED}.{BLOCKED}.184.239/viewforum.php?f=11&sid={random digit}
- http://{BLOCKED}ag.com/posting.php?mode=reply&f=11&t=1390285619&sid={random digit}
- http://{BLOCKED}ag.com/viewforum.php?f=11&sid={random digit}
- http://{BLOCKED}ng.com/posting.php?mode=reply&f=11&t=1390285619&sid={random digit}
- http://{BLOCKED}ng.com/viewforum.php?f=11&sid={random digit}
- http://{BLOCKED}lon.com/posting.php?mode=reply&f=11&t=1390285619&sid={random digit}
- http://{BLOCKED}on.com/viewforum.php?f=11&sid={random digit}
- http://{BLOCKED}rda.com/posting.php?mode=reply&f=11&t=1390285619&sid={random digit}
- http://{BLOCKED}rda.com/viewforum.php?f=11&sid={random digit}
- http://{BLOCKED}z.com/posting.php?mode=reply&f=11&t=1390285619&sid={random digit}
- http://{BLOCKED}z.com/viewforum.php?f=11&sid={random digit}
- http://{BLOCKED}p.{BLOCKED}rt.com/
Information Theft
This backdoor attempts to steal stored account information used in the following installed File Transfer Protocol (FTP) clients or file manager software:
- 3D-FTP
- AceBIT
- AceFTP
- ALFTP
- BitKinex
- BlazeFtp
- BulletProof FTP
- ClassicFTP
- CoffeeCup Software
- Cyberduck
- DeluxeFTP
- Directory Opus
- EasyFTP
- ExpanDrive
- FarManager
- FFFTP
- FileZilla
- FlashFXP
- Fling FTP
- FreshFTP
- FTP Commander
- FTP Explorer
- FTP Navigator
- FTPGetter
- FTPNow
- FTPRush
- FTPShell
- FTPVoyager
- FTPWare
- GlobalSCAPE CuteFTP 6 Home
- GlobalSCAPE CuteFTP 7 Home
- GlobalSCAPE CuteFTP 8 Home
- GlobalSCAPE CuteFTP
- GlobalSCAPE CuteFTP 8 Professional
- GlobalSCAPE CuteFTP 6 Professional
- GlobalSCAPE CuteFTP 7 Professional
- GlobalSCAPE CuteFTP Lite
- GlobalSCAPE CuteFTP Pro
- GoFTP
- LeapFTP
- LeechFTP
- LinasFTP
- My FTP
- NetDrive
- NetSarang
- NexusFile
- NovaFTP
- PuTTY
- RhinoSoft
- Robo-FTP
- SecureFX
- SmartFTP
- SoftX FTP
- Staff-FTP
- Titan FTP
- Total Commander
- TurboFTP
- UltraFXP
- WinFTP
- WinSCP
- WS_FTP
It attempts to steal stored email credentials from the following:
- IncrediMail
- Outlook
- PocoMail
- The Bat!
- Thunderbird
- Windows Live Mail
- Windows Mail
It attempts to get stored information such as user names, passwords, and hostnames from the following browsers:
- Epic Browser
- Flock
- K-Meleon
- Mozilla Firefox
- SeaMonkey
NOTES:
It checks for the presence of the following security-related directories in %Program Files% and %All Users Profile%\Application Data:
- %System Root%:\Documents and Settings\NetworkService\Local Settings\Application Data\F-SecureF-Secure Internet Security
- a-squared Anti-Malware
- a-squared HiJackFree
- Agnitum
- Alwil Software
- AnVir Task Manager
- ArcaBit
- AVAST Software
- AVG
- avg8
- Avira GmbH
- Avira
- BitDefender
- BlockPost
- Common Files\Doctor Web
- Common Files\G DATA
- Common Files\P Tools
- Common Files\Symantec Shared
- DefenseWall
- DefenseWall HIPS
- Doctor Web
- DrWeb
- ESET
- f-secure
- FRISK Software
- G DATA
- K7 Computing
- Kaspersky Lab Setup Files
- Kaspersky Lab
- Lavasoft
- Malwarebytes
- Malwarebytes' Anti-Malware
- McAfee
- McAfee.com
- Microsoft Security Client
- Microsoft Security Essentials
- Microsoft\Microsoft Antimalware
- Norton AntiVirus
- Online Solutions
- P Tools Internet Security
- P Tools
- Panda Security
- Positive Technologies
- Sandboxie
- Security Task Manager
- Spyware Terminator
- Sunbelt Software
- Symantec
- Trend Micro
- UAenter
- Vba32
- Xore
- Zillya Antivirus
It can only perform its intended routine once it is injected in the following processes:
- iexplore.exe
- firefox.exe
- explorer.exe
- chrome.exe
SOLUTION
9.300
10.882.03
24 Jun 2014
10.883.00
24 Jun 2014
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
Restart in Safe Mode
Step 3
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
- AppDataLow
- AppDataLow
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
- {malware filename} = "regsvr32.exe /s "{malware path}\{malware filename}.dll""
- {malware filename} = "regsvr32.exe /s "{malware path}\{malware filename}.dll""
- In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main
- NoProtectedModebanner = "1"
- NoProtectedModebanner = "1"
- In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main
- TabProcGrowth = "0"
- TabProcGrowth = "0"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\3
- 2500 = "3"
- 2500 = "3"
Step 5
Restart in normal mode and scan your computer with your Trend Micro product for files detected as BKDR_VAWTRAK.YZY. 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 6
Restore this deleted registry key/value from backup
*Note: Only Microsoft-related keys/values will be restored. If the malware/grayware also deleted registry keys/values related to programs that are not from Microsoft, please reinstall those programs on your computer.
- HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\Safer\CodeIdentifiers\0\Paths
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