Modified by: Alvin Bacani
ALIASES:

Worm:Win32/Neeris.gen!D (Microsoft); Spy-Agent.eq!MS08-067 (McAfee); W32.Spybot.Worm (Symantec); Net-Worm.Win32.Kolab.fbl (Kaspersky); Backdoor.Win32.EggDrop.bmg (v) (Sunbelt); Trojan.Generic.2314165 (FSecure)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

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

  • Threat Type: Worm

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

Infection Channel: Dropped by other malware, Downloaded from the Internet, Propagates via removable drives

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 drops an AUTORUN.INF file to automatically execute the copies it drops when a user accesses the drives of an affected system.

It also has rootkit capabilities, which enables it to hide its processes and files from the user.

  TECHNICAL DETAILS

File Size: 67,584 bytes
File Type: EXE
Memory Resident: Yes
Initial Samples Received Date: 21 Apr 2012
Payload: Compromises system security

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 copies of itself into the affected system:

  • %Windows%\system\svhost.exe

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

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
WSVCHO = "%Windows%\system\svhost.exe"

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 entries:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\sysdrv32
Type = "1"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\sysdrv32
Start = "3"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\sysdrv32
ErrorControl = "0"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\sysdrv32
ImagePath = "\??\%System%\drivers\sysdrv32.sys"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\sysdrv32
DisplayName = "Play Port I/O Driver"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\sysdrv32
Group = "SST wanport drivers"

Other System Modifications

This worm adds the following registry keys:

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\SafeBoot\Minimal\
SVCWINSPOOL

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\SafeBoot\Network\
SVCWINSPOOL

It adds the following registry entries:

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\AuthorizedApplications\
List
%System%\svhost.exe = "%System%\svhost.exe:*:Microsoft Enabled"

Propagation

This worm drops the following copy(ies) of itself in all removable drives:

  • wlan.exe

It drops an AUTORUN.INF file to automatically execute the copies it drops when a user accesses the drives of an affected system.

Backdoor Routine

This worm connects to the following URL(s) to send and receive commands from a remote malicious user:

  • https://a.{BLOCKED}rd.com

Rootkit Capabilities

This worm also has rootkit capabilities, which enables it to hide its processes and files from the user.

Dropping Routine

This worm drops the following files:

  • %System%\drivers\sysdrv32.sys - detected as RTKT_TCPAGENT.W

(Note: %System% is the Windows system folder, which is usually C:\Windows\System32.)

  SOLUTION

Minimum Scan Engine: 9.300
FIRST VSAPI PATTERN FILE: 7.852.05
FIRST VSAPI PATTERN DATE: 22 Feb 2012
VSAPI OPR PATTERN File: 7.853.00
VSAPI OPR PATTERN Date: 22 Feb 2012

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

[ Learn More ]

Step 3

Delete this registry key

[ 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\SYSTEM\CurrentControlSet\Services
    • sysdrv32
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SafeBoot\Minimal
    • SVCWINSPOOL
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SafeBoot\Network
    • SVCWINSPOOL

Step 4

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
    • WSVCHO = "%Windows%\system\svhost.exe"
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\AuthorizedApplications\List
    • %Windows%\system\svhost.exe = "%Windows%\system\svhost.exe:*:Microsoft Enabled"

Step 5

Search and delete this file

[ Learn More ]
There may be some files that are hidden. Please make sure you check the Search Hidden Files and Folders checkbox in the "More advanced options" option to include all hidden files and folders in the search result.
  • %System%\drivers\sysdrv32.sys

Step 6

Restart in normal mode and scan your computer with your Trend Micro product for files detected as WORM_NEERIS.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 this Knowledge Base page for more information.


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