Worm.Win32.SIPHOST.A
BehavesLike.Win32.Rontokbro.nm (MacAffee)
Windows

Threat Type: Worm
Destructiveness: No
Encrypted: Yes
In the wild: Yes
OVERVIEW
Downloaded from the Internet
This Worm arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.
It does not have any backdoor routine.
TECHNICAL DETAILS
37,888 bytes
EXE
Yes
31 Jul 2019
Connects to URLs/IPs
Arrival Details
This Worm 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 Worm drops the following files:
- %User Startup%\powershell.lnk -> Targets %Application Data%\sihost.exe
- %Application Data%\myruntme.dll -> Copy of dll loaded by Malware to proceed with its intended routine
- {Removable Drive}:\myruntme.dll -> Copy of dll loaded by Malware to proceed with its intended routine
(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Roaming on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)
It drops the following copies of itself into the affected system:
- %Application Data%\sihost.exe
(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Roaming on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)
Propagation
This Worm drops the following copy(ies) of itself in all removable drives:
- {Removable Drive}:\{Username} Photo.exe
Backdoor Routine
This Worm does not have any backdoor routine.
Rootkit Capabilities
This Worm does not have rootkit capabilities.
Download Routine
This Worm connects to the following website(s) to download and execute a malicious file:
- http://mmproject/{BLOCKED}dario.com/ntu.dat
It saves the files it downloads using the following names:
- %Application Data%\ntuser.dat
(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Roaming on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)
Information Theft
This Worm gathers the following data:
- {Computer Name}
- {User Name}
Other Details
This Worm checks for the presence of the following process(es):
- TCPVIEW - Sysinternals
- Process Monitor
- OLLYDBG
- PortmonClass
- gdkWindowTopLevel
- 18467-41
It does the following:
- Sends output of "ntuser.dat" as an attachment of the email
- The email contains the following information:
To: : m.{BLOCKED}t@india.com
Body:"Dear Sir/Madam,
This is my mmp file."
SMTP Server: smtp.{BLOCKED}.com
Attachment: {Computer Name}-{User Name}-data.zip - Checks for the presence of process with the following strings:
VIRTUAL
VMWARE
VBOX
It checks if the following virtual machine- or sandbox-related registry keys are present in the affected system:
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Servoces\Disk
Enum = {0 or 1}
It does not exploit any vulnerability.
NOTES:
However, as of this writing, the said sites are inaccessible.
SOLUTION
9.850
15.244.04
19 Jul 2019
15.245.00
20 Jul 2019
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
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 Worm.Win32.SIPHOST.A
- 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
Search and delete these files
- %User Startup%\powershell.lnk
- %Application Data%\myruntme.dll
- {Removable Drive}:\myruntme.dll
Step 5
Scan your computer with your Trend Micro product to delete files detected as Worm.Win32.SIPHOST.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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