WORM_NEERIS.H

 Analysis by: Sabrina Lei Sioting

 PLATFORM:

Windows 2000, XP, Server 2003

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 REPORTED INFECTION:

  • Threat Type: Worm

  • Destructiveness: No

  • Encrypted: No

  • In the wild: Yes


  TECHNICAL DETAILS

File Size:

77,312 bytes

File Type:

PE

Memory Resident:

Yes

Initial Samples Received Date:

19 Apr 2010

Installation

This worm drops the following copies of itself into the affected system:

  • %Windows%\system\dllcache.exe

(Note: %Windows% is the Windows folder, which is usually C:\Windows or C:\WINNT.)

It drops and executes the following files:

  • %System%\drivers\sysdrv32.sys - detected by Trend Micro as HKTL_TCPAGENT

(Note: %System% is the Windows system folder, which is usually C:\Windows\System on Windows 98 and ME, C:\WINNT\System32 on Windows NT and 2000, or C:\Windows\System32 on Windows XP and Server 2003.)

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
netmon = %Windows%\system\dllcache.exe

Other System Modifications

This worm creates the following registry entry(ies) to bypass Windows Firewall:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\AuthorizedApplications\
List
%Windows%\\system\\dllcache.exe = %Windows%\system\dllcache.exe:*:Microsoft Enabled

  SOLUTION

Minimum Scan Engine:

8.900

VSAPI OPR PATTERN File:

07.112.06

VSAPI OPR PATTERN Date:

19 Apr 2010

Step 1

For Windows XP and Windows Server 2003 users, before doing any scans, please make sure you disable System Restore to allow full scanning of your computer.

Step 2

Remove malware files dropped/downloaded by WORM_NEERIS.H

     HKTL_TCPAGENT

Step 3

Delete this registry value

[ Learn More ]

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\CurrentVersion\Run
    • netmon = %Windows%\system\dllcache.exe
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SharedAccess\Parameters\FiewallPolicy\StandardProfile\AuthorizedApplications\List
    • %Windows%\system\dllcache.exe = %WINDOWS%\system\dllcache.exe:*:Microsoft Enabled

Step 4

Scan your computer with your Trend Micro product to delete files detected as WORM_NEERIS.H. 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.


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