Backdoor.Win32.IRCBOT.SMDA1
Backdoor:Win32/IRCbot (Microsoft); W32/IRCbot.g.gen.b (McAfee); W32.IRCBot (Symantec); Backdoor.Win32.IRCBot.qz (Kaspersky); Troj/Agent-BCHK (Sophos); Trojan.Win32.Generic!BT (Sunbelt)
Windows
![](/vinfo/imgFiles/legend.jpg)
Threat Type: Backdoor
Destructiveness: No
Encrypted:
In the wild: Yes
OVERVIEW
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 disables Task Manager, Registry Editor, and Folder Options.
TECHNICAL DETAILS
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 adds the following processes:
- reg.exe import %Windows%\regedit.reg
- reg.exe export HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\srservice %Windows%\regedit.reg
- winzip32.exe -min -a -en -r "%System Root%\Users\Public\Music\angle.Zip" "%System Root%\Users\Public\Music\angle.eXe"
- rar.exe a -ao -ep "%System Root%\Users\Public\Music\angle.Zip" "%System Root%\Users\Public\Music\angle.eXe"
- %System Root%\Users\Public\Pictures\svchost.eXe
- %System Root%\Users\Public\Music\svchost.eXe
- %All Users Profile%\Microsoft\Windows\Start Menu\Programs\Startup\msmsgs.eXe
- %System%\angle.eXe
(Note: %Windows% is the Windows folder, where it usually is C:\Windows on all Windows operating system versions.. %System Root% is the Windows root folder, where it usually is C:\ on all Windows operating system versions.. %All Users Profile% is the common user's profile folder, which is usually C:\Documents and Settings\All Users on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\ProgramData on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit). . %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)
Other System Modifications
This Backdoor modifies the following file(s):
- %System Root%\Users\Public\Music\RCX1812.tmp
- %System Root%\Users\Public\Pictures\RCXCA21.tmp
- F:\data\RCXA565.tmp
- %Windows%\RCX162E.tmp
- %System Root%\Users\Public\Music\RCX3DFA.tmp
- %System Root%\Users\Public\Music\RCXCB0C.tmp
- %System Root%\Users\Public\Music\RCX167E.tmp
- %System Root%\Users\Public\Music\RCXCCC4.tmp
- F:\RCXA602.tmp
- %Windows%\RCX15F0.tmp
- %System Root%\Users\Public\Pictures\RCX1366.tmp
- %Windows%\RCXEBC9.tmp
- %Windows%\RCX3D9B.tmp
- %System Root%\Users\Public\Pictures\RCX1432.tmp
- %Windows%\RCXCB5B.tmp
(Note: %System Root% is the Windows root folder, where it usually is C:\ on all Windows operating system versions.. %Windows% is the Windows folder, where it usually is C:\Windows on all Windows operating system versions.)
It adds the following registry entries:
HKEY_CURRENT_USER\Software\Policies\
Microsoft\Windows\System
DisableCMD = "2"
It modifies the following registry entries:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
Hidden = "2"
(Note: The default value data of the said registry entry is 2.)
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
HideFileExt = "1"
(Note: The default value data of the said registry entry is 1.)
It creates the following registry entry(ies) to disable Task Manager, Registry Tools and Folder Options:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Policies\
Explorer
NoSetFolders = "1"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Policies\
System
DisableRegistryTools = "2"
Dropping Routine
This Backdoor drops the following files:
- F:\mail_client'.eXe
- %System Root%\Users\Public\Music\RCX3DFA.tmp
- F:\~angle.eXe
- %System Root%\Users\Public\Music\RCXCCC4.tmp
- F:\wlines.eXe
- F:\data\~data.exe
- F:\data\photos\~photos.exe
- %Windows%\RCX162E.tmp
- %System Root%\Users\Public\Music\svchost.eXe
- %System Root%\Users\Public\Music\RCX167E.tmp
- F:\RCXA602.tmp
- %Windows%\RCX15F0.tmp
- %System Root%\Users\Public\Pictures\RCX1366.tmp
- %Windows%\RCXEBC9.tmp
- %Windows%\ziprar.eXe
- F:\data\photos\long_exposure.eXe
- %System Root%\Users\Public\Music\RCX1812.tmp
- %Windows%\svchost.eXe
- F:\data\photos\stunning.eXe
- %System Root%\Users\Public\Music\RCXCB0C.tmp
- %System Root%\Users\Public\Pictures\iexplore.eXe
- %System%\RCX167D.tmp
- %System Root%\Surat Buat Presiden.htm
- %System%\angle.eXe
- %System Root%\Users\Public\Pictures\RCX1432.tmp
- %Windows%\RCXCB5B.tmp
- %System Root%\Users\Public\Pictures\wmplayer.eXe
- %System Root%\Users\Public\Pictures\svchost.eXe
- %System Root%\Users\Public\Pictures\RCXCA21.tmp
- F:\data\RCXA565.tmp
- F:\data\WinLines'.eXe
- %System%\RCX162F.tmp
- %Windows%\RCX3D9B.tmp
- %System%\RCXCB8B.tmp
- %System Root%\Users\Public\Music\angle.eXe
- %System Root%\Users\Public\Pictures\jpg.eXe
- %All Users Profile%\Microsoft\Windows\Start Menu\Programs\Startup\msmsgs.eXe
(Note: %System Root% is the Windows root folder, where it usually is C:\ on all Windows operating system versions.. %Windows% is the Windows folder, where it usually is C:\Windows on all Windows operating system versions.. %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.. %All Users Profile% is the common user's profile folder, which is usually C:\Documents and Settings\All Users on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\ProgramData on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit). )
This report is generated via an automated analysis system.
SOLUTION
Step 1
Before doing any scans, Windows 7, Windows 8, Windows 8.1, and Windows 10 users must disable System Restore to allow full scanning of their computers.
Step 2
Identify and terminate files detected as Backdoor.Win32.IRCBOT.SMDA1
- 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 3
Enable Registry Editor, Task Manager, and Folder options
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\Policies\Microsoft\Windows\System
- DisableCMD = "2"
Step 5
Restore these modified registry values
Important:Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this only if you know how to or you can seek your system administrator's help. You may also check out this Microsoft article first before modifying your computer's registry.
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced
- From: Hidden = "2"
To: Hidden = ""2""
- From: Hidden = "2"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced
- From: HideFileExt = "1"
To: HideFileExt = ""1""
- From: HideFileExt = "1"
Step 6
Search and delete these components
- F:\mail_client'.eXe
- %System Root%\Users\Public\Music\RCX3DFA.tmp
- F:\~angle.eXe
- %System Root%\Users\Public\Music\RCXCCC4.tmp
- F:\wlines.eXe
- F:\data\~data.exe
- F:\data\photos\~photos.exe
- %Windows%\RCX162E.tmp
- %System Root%\Users\Public\Music\svchost.eXe
- %System Root%\Users\Public\Music\RCX167E.tmp
- F:\RCXA602.tmp
- %Windows%\RCX15F0.tmp
- %System Root%\Users\Public\Pictures\RCX1366.tmp
- %Windows%\RCXEBC9.tmp
- %Windows%\ziprar.eXe
- F:\data\photos\long_exposure.eXe
- %System Root%\Users\Public\Music\RCX1812.tmp
- %Windows%\svchost.eXe
- F:\data\photos\stunning.eXe
- %System Root%\Users\Public\Music\RCXCB0C.tmp
- %System Root%\Users\Public\Pictures\iexplore.eXe
- %System%\RCX167D.tmp
- %System Root%\Surat Buat Presiden.htm
- %System%\angle.eXe
- %System Root%\Users\Public\Pictures\RCX1432.tmp
- %Windows%\RCXCB5B.tmp
- %System Root%\Users\Public\Pictures\wmplayer.eXe
- %System Root%\Users\Public\Pictures\svchost.eXe
- %System Root%\Users\Public\Pictures\RCXCA21.tmp
- F:\data\RCXA565.tmp
- F:\data\WinLines'.eXe
- %System%\RCX162F.tmp
- %Windows%\RCX3D9B.tmp
- %System%\RCXCB8B.tmp
- %System Root%\Users\Public\Music\angle.eXe
- %System Root%\Users\Public\Pictures\jpg.eXe
- %All Users Profile%\Microsoft\Windows\Start Menu\Programs\Startup\msmsgs.eXe
Step 7
Scan your computer with your Trend Micro product to delete files detected as Backdoor.Win32.IRCBOT.SMDA1. 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:
Step 8
Restore deleted/modified files and/or registry entries from backup
*Note: Only Microsoft-related files/keys/values will be restored. If this malware/grayware also deleted registry keys/values related to programs that are not from Microsoft, please reinstall those programs on your computer.
- %System Root%\Users\Public\Music\RCX1812.tmp
- %System Root%\Users\Public\Pictures\RCXCA21.tmp
- F:\data\RCXA565.tmp
- %Windows%\RCX162E.tmp
- %System Root%\Users\Public\Music\RCX3DFA.tmp
- %System Root%\Users\Public\Music\RCXCB0C.tmp
- %System Root%\Users\Public\Music\RCX167E.tmp
- %System Root%\Users\Public\Music\RCXCCC4.tmp
- F:\RCXA602.tmp
- %Windows%\RCX15F0.tmp
- %System Root%\Users\Public\Pictures\RCX1366.tmp
- %Windows%\RCXEBC9.tmp
- %Windows%\RCX3D9B.tmp
- %System Root%\Users\Public\Pictures\RCX1432.tmp
- %Windows%\RCXCB5B.tmp
Did this description help? Tell us how we did.