BKDR_NEUREVT.JSJ
a variant of Win32/Kryptik.BAJC trojan (NOD32), W32/Krptik.QWR!tr (Fortinet)
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: Trojan
Destructiveness: No
Encrypted: Yes
In the wild: Yes
OVERVIEW
Downloaded from the Internet, Dropped by other malware
This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.
It executes commands from a remote malicious user, effectively compromising the affected system. It connects to a website to send and receive information.
It modifies the Internet Explorer Zone Settings.
It retrieves specific information from the affected system.
It deletes the initially executed copy of itself.
TECHNICAL DETAILS
354,304 bytes
EXE
Yes
08 May 2013
Compromises system security, Terminates processes, Steals information
Arrival Details
This Trojan 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 Trojan drops the following copies of itself into the affected system:
- {Path}\jewsdidit{number}\{random file name 1}.exe
It drops the following non-malicious file:
- {Path}\jewsdidit{number}\{random file name 2}.txt
It injects codes into the following process(es):
- wuauclt.exe
Autostart Technique
This Trojan adds the following registry entries to enable its automatic execution at every system startup:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
jewsdidit = "{Path}\jewsdidit{number}\{random file name 1}.exe"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
jewsdidit = "{Path}\jewsdidit{number}\{random file name 1}.exe"
Other System Modifications
This Trojan adds the following registry entries:
HKEY_CURRENT_USER\CLSID\{CLSID}\
{random value}\CG1
HAL = "{random values}"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
ShowSuperHidden = "0"
HKEY_LOCAL_MACHINE\SOFTWARE\Win7zip
Uuid = "{random values}"
Backdoor Routine
This Trojan executes the following commands from a remote malicious user:
- Download and execute files
- Perform Slowloris flooding
- Execute shell commands
- Copy itself in removable drives
- Open a URL
- Uninstall itself
It connects to the following websites to send and receive information:
- {BLOCKED}y.{BLOCKED}s.cat/h/order.php
- {BLOCKED}y.{BLOCKED}s.es/h/order.php
- {BLOCKED}y.{BLOCKED}t.net/h/order.php
Web Browser Home Page and Search Page Modification
This Trojan modifies the Internet Explorer Zone Settings.
Information Theft
This Trojan retrieves the following information from the affected system:
- Operating system version
- CPU information
- Information on installed FTPs
- Installed applications
Other Details
This Trojan connects to the following URL(s) to check for an Internet connection:
- update.microsoft.com
- microsoft.com
- windowsupdate.microsoft.com
- google.com
It deletes the initially executed copy of itself
NOTES:
{Path} can be any of the following:
- %All Users Profile%
- %Program Files%\Common Files
It disables the following antivirus-related applications by adding the following registry entries:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Image File Execution Options\{application}
Debugger = "{random characters}_.exe"
- a2guard.exe
- a2service.exe
- a2start.exe
- adaware.exe
- ALUpdate.exe
- arcaclean.exe
- avastsvc.exe
- avastui.exe
- avcenter.exe
- AVENGINE.exe
- avgcfgex.exe
- avgdiagex.exe
- avgidsagent.exe
- avgmfapx.exe
- avgnt.exe
- avguard.exe
- avgui.exe
- avgupd.exe
- avgwdsvc.exe
- AVK.exe
- AVKTray.exe
- avshadow.exe
- BgScan.exe
- BullGuard.exe
- BullGuardBhvScanner.exe
- BullGuardScanner.exe
- BullGuardUpdate.exe
- BullGuardUpdate2.exe
- ccsvchst.exe
- ccupdate.exe
- CLPSLA.exe
- coreFrameworkHost.exe
- coreServiceShell.exe
- egui.exe
- ekrn.exe
- epavjobs.exe
- ForceField.exe
- FProtTray.exe
- FPWin.exe
- fshoster32.exe
- GDFirewallTray.exe
- GDSC.exe
- K7TSUpdT.exe
- mbam.exe
- mbamgui.exe
- mcagent.exe
- McPvTray.exe
- mcshell.exe
- mcshield.exe
- McSvHost.exe
- McUICnt.exe
- mcupdate.exe
- mcupdmgr.exe
- MSASCui.exe
- MsMpEng.exe
- msseces.exe
- niu.exe
- op_mon.exe
- pctsAuxs.exe
- pctsGui.exe
- pctsSvc.exe
- PSANHost.exe
- PSUAService.exe
- PSUNMain.exe
- RavMonD.exe
- rcfp.exe
- rsmain.exe
- RsMgrSvc.exe
- RsTray.exe
- SBAMTray.exe
- sbamui.exe
- sguardxup.exe
- starter_avp.exe
- symerr.exe
- uiSeAgnt.exe
- uiWatchDog.exe
- Update.exe
- update_tmp.exe
- updater.exe
- Upgrader.exe
- usrreq.exe
- uWinMgr.exe
- WRSA.exe
- zatray.exe
It attempts to gather account information from the following applications:
- CoreFTP
- FileZilla
- FlashFXP
- FTP Commander
- PuTTY
- Skype
- SmartFTP
- WinSCP
It queries the following registry key to get the processor information:
HKEY_LOCAL_MACHINE\HARDWARE\DESCRIPTION\System\CentralProcessor
SOLUTION
9.300
9.902.07
08 May 2013
9.903.00
08 May 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 BKDR_NEUREVT.JSJ
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_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Image File Execution Options\{application}
- Debugger = "{random characters}_.exe"
- Debugger = "{random characters}_.exe"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
- jewsdidit = "{Path}\jewsdidit{number}\{random filename 1}.exe"
- jewsdidit = "{Path}\jewsdidit{number}\{random filename 1}.exe"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
- jewsdidit = "{Path}\jewsdidit{number}\{random filename 1}.exe"
- jewsdidit = "{Path}\jewsdidit{number}\{random filename 1}.exe"
- In HKEY_CURRENT_USER\CLSID\{CLSID}\{random value}\CG1
- HAL = "{random values}"
- HAL = "{random values}"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced
- ShowSuperHidden = "0"
- ShowSuperHidden = "0"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Win7zip
- Uuid = "{random values}"
- Uuid = "{random values}"
Step 5
Search and delete this file
There may be some component files that are hidden. Please make sure you check the Search Hidden Files and Folders checkbox in the More advanced options option to include all hidden files and folders in the search result.
- {Path}\jewsdidit{number}\{random file name 2}.txt
Step 6
Restart in normal mode and scan your computer with your Trend Micro product for files detected as BKDR_NEUREVT.JSJ. 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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