Trojan.Win32.RONJOB.A
BScope.Trojan.Packed (VBA32)
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:
- %Windows%\Help\__tmp_rar_sfx_access_check_{Random Characters} -> deleted afterwards
- %Windows%\Help\ic.exe -> detected as Trojan.Win32.RONJOB.B
- %Windows%\Help\WINWORD.EXE
- %User Temp%\edg{Random Characters}.tmp
- %User Temp%\edg{Random Characters + 1}.tmp -> copy of %Windows%\Help\wwlib.dll
- %User Temp%\edg{Random Characters + 2}.tmp -> copy of %Windows%\Help\ic.exe
- %Windows%\Help\wwlib.dll
It adds the following processes:
- "%Windows%\help\ic.exe"
- "%Windows%\help\WINWORD.EXE"
- net start "Bonjours"
(Note: %Windows% is the Windows folder, where it usually is C:\Windows on all Windows operating system versions.)
Autostart Technique
This Trojan registers its dropped component as a system service to ensure its automatic execution at every system startup. It does this by creating the following registry entries:
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
services\Bonjours\Parameters
ServiceDll = %User Temp%\edg{Random Characters}.tmp
It registers its dropped component as a system service to ensure its automatic execution at every system startup. It does this by creating the following registry keys:
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
services\Bonjours\Parameters
Other System Modifications
This Trojan modifies the following registry entries:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Svchost
netsvcs = AeLookupSvc, CertPropSvc, SCPolicySvc, lanmanserver, gpsvc, IKEEXT, AudioSrv, FastUserSwitchingCompatibility, Ias, Irmon, Nla, Ntmssvc, NWCWorkstation, Nwsapagent, Rasauto, Rasman, Remoteaccess, SENS, Sharedaccess, SRService, Tapisrv, Wmi, WmdmPmSp, TermService, wuauserv, BITS, ShellHWDetection, LogonHours, PCAudit, helpsvc, uploadmgr, iphlpsvc, seclogon, AppInfo, msiscsi, MMCSS, wercplsupport, EapHost, ProfSvc, schedule, hkmsvc, SessionEnv, winmgmt, browser, Themes, BDESVC, AppMgmt, Bonjours
Other Details
This Trojan does the following:
- This Trojan needs to be ran with administrative rights to proceed with malicious routine
- It displays the following message box when it isn't ran with administrative rights:
SOLUTION
Step 1
Trend Micro Predictive Machine Learning detects and blocks malware at the first sign of its existence, before it executes on your system. When enabled, your Trend Micro product detects this malware under the following machine learning name:
- Troj.Win32.TRX.XXPE50FSX009
Step 2
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 3
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 4
Search and delete this file
- %Windows%\Help\wwlib.dll
- %Windows%\Help\ic.exe
- %Windows%\Help\WINWORD.EXE
- %User Temp%\edg{Random Characters}.tmp
- %User Temp%\edg{Random Characters + 1}.tmp
- %User Temp%\edg{Random Characters + 2}.tmp
Step 5
Restore this modified 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\Svchost
- From: netsvcs = "AeLookupSvc, CertPropSvc, SCPolicySvc, lanmanserver, gpsvc, IKEEXT, AudioSrv, FastUserSwitchingCompatibility, Ias, Irmon, Nla, Ntmssvc, NWCWorkstation, Nwsapagent, Rasauto, Rasman, Remoteaccess, SENS, Sharedaccess, SRService, Tapisrv, Wmi, WmdmPmSp, TermService, wuauserv, BITS, ShellHWDetection, LogonHours, PCAudit, helpsvc, uploadmgr, iphlpsvc, seclogon, AppInfo, msiscsi, MMCSS, wercplsupport, EapHost, ProfSvc, schedule, hkmsvc, SessionEnv, winmgmt, browser, Themes, BDESVC, AppMgmt, Bonjours"
- To: netsvcs = "{Default Value}"
Step 6
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.
- HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\services\Bonjours\Parameters
Step 7
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. Before you could do this, you must restart in Safe Mode. For instructions on how to do this, you may refer to this page If the preceding step requires you to restart in safe mode, you may proceed to edit the system registry.
- HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\services\Bonjours\Parameters
Step 8
Scan your computer with your Trend Micro product to delete files detected as Trojan.Win32.RONJOB.A. 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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