TROJ_NECURS.USWD
Trojan.Gen.2 (Norton) ; Trojan.GenericKD.31089208 (Bitdefender)
Windows
Threat Type: Trojan
Destructiveness: No
Encrypted: No
In the wild: Yes
OVERVIEW
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.
TECHNICAL DETAILS
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 files:
- %ProgramData%\TMPUSER.DAT -> contains the user domain (deleted afterwards)
(Note: %ProgramData% is the Program Data folder, where it usually is C:\Program Files in Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\ProgramData in 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 processes:
- %System%\cmd.exe" /C echo %USERDOMAIN% > C:\ProgramData\TMPUSER.DAT -> to check the user domain
- cmd /C net.exe stop ammyy
- cmd /C sc delete ammyy
- cmd /C net.exe stop foundation
- cmd /C sc delete foundation
Other System Modifications
This Trojan deletes the following files:
- %ProgramData%\AMMYY\wmihost.exe
- %ProgramData%\AMMYY\settings3.bin
- %ProgramData%\Foundation\wmites.exe
- %ProgramData%\Foundation\settings3.bin
- %ProgramData%\Foundation1\wmites.exe
- %ProgramData%\Foundation1\settings3.bin
- %ProgramData%\Microsoft\wsus.exe
- %ProgramData%\Microsoft\settings3.bin
- %ProgramData%\Microsoft Help\wsus.exe
- %ProgramData%\Microsoft Help\settings3.bin
(Note: %ProgramData% is the Program Data folder, where it usually is C:\Program Files in Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\ProgramData in 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 deletes the following folders:
- %ProgramData%\settings
- %ProgramData%\Microsoft\Enc
- %ProgramData%\AMMYY
- %ProgramData%\Foundation
- %ProgramData%\Foundation1
(Note: %ProgramData% is the Program Data folder, where it usually is C:\Program Files in Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\ProgramData in 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.)
Process Termination
This Trojan terminates processes or services that contain any of the following strings if found running in the affected system's memory:
- wsus.exe
Download Routine
This Trojan connects to the following website(s) to download and execute a malicious file:
- http://{BLOCKED}.{BLOCKED}.129.117/Yjdfel765Hs -> Detected as BKDR_FLAWEDAMMYY.D
Other Details
This Trojan does the following:
- Will not proceed to its intended routine if any of the following processes is running:
- BDSS.exe
- BullGuard.exe
- bdss.exe
- bdagent.exe
- V3Main.exe
- V3SP.exe
- PSUAMain.exe
- Check if debugger is present
- The malware will terminate if any of the following processes is running on the infected machine:
- QHACTIVEDEFENSE.EXE
- QHSAFETRAY.EXE
- QHWATCHDOG.EXE
- CMDAGENT.EXE
- CIS.EXE
- V3LITE.EXE
- V3MAIN.EXE
- V3SP.EXE
- SPIDERAGENT.EXE
- DWENGINE.EXE
- DWARKDAEMON.EXE
- EGUI.EXE
- EKRN.EXE
- Will only proceed to its intended routine if the User Domain contains the following string:
- banc
- bank
- aloha
- aldelo
- postilion
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
Identify and terminate files detected as TROJ_NECURS.USWD
- Windows Task Manager may not display all running processes. In this case, please use a third-party process viewer, preferably Process Explorer, to terminate the malware/grayware/spyware file. You may download the said tool here.
- If the detected file is displayed in either Windows Task Manager or Process Explorer but you cannot delete it, restart your computer in safe mode. To do this, refer to this link for the complete steps.
- If the detected file is not displayed in either Windows Task Manager or Process Explorer, continue doing the next steps.
Step 4
Scan your computer with your Trend Micro product to delete files detected as TROJ_NECURS.USWD. 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 the following Trend Micro Support pages for more information:
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