Worm:Win32/Mywife.E@mm!CME24 (Microsoft), PAK:UPX, Email-Worm.Win32.Nyxem.e, Email-Worm.Win32.Nyxem.e (Kaspersky), W32.Blackmal.E@mm (Symantec), W32/MyWife.d@MM!M24 (McAfee), W32/Nyxem-D (Sophos), Email-Worm:W32/W32.Nyxem.E (Fsecure), Email-Worm.Win32.Mywife.gen (Sunbelt), Worm.Nyxem.E (Clamav),
Windows 2000, Windows XP, Windows Server 2003
This Worm arrives as attachment to mass-mailed email messages. It arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.
It uses the Windows Task Scheduler to add a scheduled task that executes the copies it drops. It bears the file icons of certain applications to avoid easy detection and consequent removal.
It disables the user's mouse and keyboard. This prevents users from removing this malware from the affected computer.
Arrival Details
This Worm arrives as attachment to mass-mailed email messages.
It may arrive via network shares.
It 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 copies of itself into the affected system:
(Note: %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.. %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.)
It drops the following non-malicious files:
(Note: %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)
It uses the Windows Task Scheduler to add a scheduled task that executes the copies it drops.
It bears the file icons of the following applications:
It terminates the execution of the copy it initially executed and executes the copy it drops instead.
Autostart Technique
This Worm adds the following registry entries to enable its automatic execution at every system startup:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
ScanRegistry = "scanregw.exe /scan"
The scheduled task executes the malware at the following period:
Other System Modifications
This Worm adds the following registry entries as part of its installation routine:
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Licenses
{default} = "Licensing: Copying the keys may be a violation of established copyrights."
It modifies the following registry key(s)/entry(ies) as part of its installation routine:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
WebView = "0"
(Note: The default value data of the said registry entry is 1.)
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
CabinetState
FullPath = "1"
(Note: The default value data of the said registry entry is 0.)
It adds the following registry keys as part of its installation routine:
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Licenses\096EFC40-6ABF-11cf-850C-08002B30345D
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Licenses\190B7910-992A-11cf-8AFA-00AA00C00905
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Licenses\2c49f800-c2dd-11cf-9ad6-0080c7e7b78d
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Licenses\4250E830-6AC2-11cf-8ADB-00AA00C00905
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Licenses\4D553650-6ABE-11cf-8ADB-00AA00C00905
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Licenses\556C75F1-EFBC-11CF-B9F3-00A0247033C4
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Licenses\57CBF9E0-6AA7-11cf-8ADB-00AA00C00905
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Licenses\5f54e750-ce26-11cf-8e43-00a0c911005a
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Licenses\6FB38640-6AC7-11cf-8ADB-00AA00C00905
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Licenses\72E67120-5959-11cf-91F6-C2863C385E30
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Licenses\78E1BDD1-9941-11cf-9756-00AA00C00908
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Licenses\7C35CA30-D112-11cf-8E72-00A0C90F26F8
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Licenses\899B3E80-6AC6-11cf-8ADB-00AA00C00905
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Licenses\9E799BF1-8817-11cf-958F-0020AFC28C3B
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Licenses\B1EFCCF0-6AC1-11cf-8ADB-00AA00C00905
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Licenses\BC96F860-9928-11cf-8AFA-00AA00C00905
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Licenses\E32E2733-1BC5-11d0-B8C3-00A0C90DCA10
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Licenses\F4FC596D-DFFE-11CF-9551-00AA00A3DC45
It modifies the following registry entries to hide files with Hidden attributes:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
ShowSuperHidden = "0"
(Note: The default value data of the said registry entry is 1.)
It disables the user's mouse and keyboard.
Propagation
This Worm searches the network for the following shared networks onto which it attempts to drop copies of itself:
It gathers target email addresses from files with the following extensions:
It avoids sending email messages to addresses containing the following strings:
Information Theft
This Worm gathers the following data:
Stolen Information
This Worm sends the gathered information via HTTP POST to the following URL:
Other Details
This Worm closes application windows that contain the following strings in the title bar:
NOTES:
Upon execution, this opens its dropped non-malicious .ZIP file %System%\{malware name}.zip in order to trick users that a legitimate .ZIP file is executed.
It deletes the following files found in the following folder:
It deletes all .DLL files found in the following folders:
It deletes all .EXE files found in the following folders:
It deletes all .PPL files found in the following folder:
It deletes all files found in the following folders:
It deletes certain registry values if found in the following registry keys:
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\RunServices
The following registry values are deleted if found in the above-mentioned registry keys:
It searches the affected system for the existence of the following registry entries:
HKEY_LOCAL_MACHINE\kyLab\InstalledProducts\Kaspersky Anti-Virus
Personal
Folder = {file path and file name}
HKEY_LOCAL_MACHINE\SOFTWARE\Symantec\InstalledApps
NAV = {file path and file name}
HKEY_LOCAL_MACHINE\Software\INTEL\LANDesk\VirusProtect6\CurrentVersion
Home Directory = {file path and file name}
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\Panda Antivirus 6.0 Platinum
InstallLocation = {file path and file name}
HKEY_LOCAL_MACHINE\SOFTWARE\KasperskyLab\Components\101
Folder = {file path and file name}
Once found, it follows the registry value data and deletes all .EXE files found in the folder listed under the registry value data.
It also searches for the existence of the following registry entry:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\App Paths\Iface.exe
Path = {file path and file name}
Once found, it follows the registry value data and deletes all .PPL files found in the folder listed under the registry value data.
It deletes all files found in the following shared folders:
On the 3rd day of the month, it searches for files with the following file extensions:
If found, it then overwrites it with the following strings:
It displays the message, Update Please wait on Window's taskbar status area and the icon of the following folder if found:
It then drops the following files:
It uses its own Simple Mail Transfer Protocol (SMTP) engine to send email messages with a copy of itself as an attachment and that contains the following information:
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
Restart in Safe Mode
Step 3
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.
Step 4
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.
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.
Step 6
Delete the Scheduled Tasks added by this malware/grayware
To delete the added Scheduled Task file:
For Windows 2000, Windows XP, and Windows Server 2003:
For Windows Vista, Windows 7, Windows Server 2008, Windows 8, Windows 8.1, and Windows Server 2012:
Step 7
Search and delete this file
Step 8
Restart in normal mode and scan your computer with your Trend Micro product for files detected as WORM_NYXEM.E. 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.
Step 9
Restore these deleted registry keys/values from backup
*Note: Only Microsoft-related keys/values will be restored. If the malware/grayware also deleted registry keys/values related to programs that are not from Microsoft, please reinstall those programs on your computer.
Step 10
Restore these deleted files from backup
*Note: Only Microsoft-related 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.