WORM_MASLAN.E


 ALIASES:

Worm:Win32/Maslan.D@mm (Microsoft); W32/Maslan.g@MM (McAfee); W32.Maslan.A@mm (Symantec); Net-Worm.Win32.Maslan.d (Kaspersky); Trojan.Win32.Generic!BT (Sunbelt); MemScan:Win32.Worm.Maslan.C (FSecure)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

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

  • Threat Type: Worm

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW


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.

  TECHNICAL DETAILS

File Size:

62,976 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

16 Mar 2012

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 creates the following folders:

  • %User Profile%\Application Data\VMware

(Note: %User Profile% is the current user's profile folder, which is usually C:\Windows\Profiles\{user name} on Windows 98 and ME, C:\WINNT\Profiles\{user name} on Windows NT, and C:\Documents and Settings\{user name} on Windows 2000, 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
Public Microsoft ODBC = "%System%\ODBC32r.exe"

Other System Modifications

This worm deletes the following files:

  • %System%\ODBC32AlaMail
  • %System%\ODBC32AlaFtp
  • %Windows%\SoftwareDistribution\DataStore\Logs\edbtmp.log

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

It adds the following registry keys:

HKEY_CURRENT_USER\SOFTWARE\Microsoft\
Protected Storage System Provider

HKEY_CURRENT_USER\SOFTWARE\Microsoft\
Protected Storage System Provider\S-1-5-20

HKEY_CURRENT_USER\Software\Microsoft\
Protected Storage System Provider\S-1-5-20\Data 2

HKEY_CURRENT_USER\Software\Microsoft\
Protected Storage System Provider\S-1-5-20\Data 2\
Windows

HKEY_CURRENT_USER\SOFTWARE\Microsoft\
Protected Storage System Provider\S-1-5-19

HKEY_CURRENT_USER\Software\Microsoft\
Protected Storage System Provider\S-1-5-19\Data 2

HKEY_CURRENT_USER\Software\Microsoft\
Protected Storage System Provider\S-1-5-19\Data 2\
Windows

It adds the following registry entries:

HKEY_CURRENT_USER\Software\Microsoft\
Protected Storage System Provider\S-1-5-20\Data 2\
Windows
Value = "{random values}"

HKEY_CURRENT_USER\Software\Microsoft\
Protected Storage System Provider\S-1-5-20
Migrate = "2"

HKEY_CURRENT_USER\Software\Microsoft\
Protected Storage System Provider\S-1-5-19\Data 2\
Windows
Value = "{random values}"

HKEY_CURRENT_USER\Software\Microsoft\
Protected Storage System Provider\S-1-5-19
Migrate = "2"

It modifies the following registry entries:

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\Eventlog\Application\
ESENT
EventMessageFile = "%System%\ESENT.dll"

(Note: The default value data of the said registry entry is {random values}.)

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\Eventlog\Application\
ESENT
CategoryMessageFile = "%System%\ESENT.dll"

(Note: The default value data of the said registry entry is {random values}.)

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\Eventlog\Application\
ESENT
CategoryCount = "1"

(Note: The default value data of the said registry entry is 10.)

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\Eventlog\Application\
ESENT
TypesSupported = "7"

(Note: The default value data of the said registry entry is 7.)

Dropping Routine

This worm drops the following files:

  • %System%\ODBC32u
  • %System%\ODBC32r.exe
  • %System%\ODBC32j.dll
  • %System%\..\ODBC32n.exe
  • %System%\ODBC32t
  • %System%\ODBC32e
  • %System%\winlogon32.dll
  • %System%\plastilin

(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.)

Other Details

This worm connects to the following possibly malicious URL:

  • http://{BLOCKED}s.com/cnt.php
  • http://{BLOCKED}s.com/with_love.dat

This report is generated via an automated analysis system.

  SOLUTION

Minimum Scan Engine:

9.200

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

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_CURRENT_USER\SOFTWARE\Microsoft
    • Protected Storage System Provider
  • In HKEY_CURRENT_USER\SOFTWARE\Microsoft\Protected Storage System Provider
    • S-1-5-20
  • In HKEY_CURRENT_USER\Software\Microsoft\Protected Storage System Provider\S-1-5-20
    • Data 2
  • In HKEY_CURRENT_USER\Software\Microsoft\Protected Storage System Provider\S-1-5-20\Data 2
    • Windows
  • In HKEY_CURRENT_USER\SOFTWARE\Microsoft\Protected Storage System Provider
    • S-1-5-19
  • In HKEY_CURRENT_USER\Software\Microsoft\Protected Storage System Provider\S-1-5-19
    • Data 2
  • In HKEY_CURRENT_USER\Software\Microsoft\Protected Storage System Provider\S-1-5-19\Data 2
    • Windows

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
    • Public Microsoft ODBC = "%System%\ODBC32r.exe"
  • In HKEY_CURRENT_USER\Software\Microsoft\Protected Storage System Provider\S-1-5-20\Data 2\Windows
    • Value = "{random values}"
  • In HKEY_CURRENT_USER\Software\Microsoft\Protected Storage System Provider\S-1-5-20
    • Migrate = "2"
  • In HKEY_CURRENT_USER\Software\Microsoft\Protected Storage System Provider\S-1-5-19\Data 2\Windows
    • Value = "{random values}"
  • In HKEY_CURRENT_USER\Software\Microsoft\Protected Storage System Provider\S-1-5-19
    • Migrate = "2"

Step 5

Restore this modified 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\SYSTEM\ControlSet001\Services\Eventlog\Application\ESENT
    • From: EventMessageFile = "%System%\ESENT.dll"
      To: EventMessageFile = ""{random values}""
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Eventlog\Application\ESENT
    • From: CategoryMessageFile = "%System%\ESENT.dll"
      To: CategoryMessageFile = ""{random values}""
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Eventlog\Application\ESENT
    • From: CategoryCount = "1"
      To: CategoryCount = ""10""
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Eventlog\Application\ESENT
    • From: TypesSupported = "7"
      To: TypesSupported = ""7""

Step 6

Search and delete these files

[ Learn More ]
There may be some component 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%\ODBC32u
  • %System%\ODBC32r.exe
  • %System%\ODBC32j.dll
  • %System%\..\ODBC32n.exe
  • %System%\ODBC32t
  • %System%\ODBC32e
  • %System%\winlogon32.dll
  • %System%\plastilin

Step 7

Search and delete this folder

[ Learn More ]
Please make sure you check the Search Hidden Files and Folders checkbox in the More advanced options option to include all hidden folders in the search result.
  • %User Profile%\Application Data\VMware

Step 8

Restart in normal mode and scan your computer with your Trend Micro product for files detected as WORM_MASLAN.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 this file from backup only Microsoft-related files will be restored. If this malware/grayware also deleted files related to programs that are not from Microsoft, please reinstall those programs on you computer again.

  • %System%\ODBC32AlaMail
  • %System%\ODBC32AlaFtp
  • %Windows%\SoftwareDistribution\DataStore\Logs\edbtmp.log


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