WORM_UTOTI.JTB

 Analysis by: Marfel Tiamzon
 Modified by: Michael Cabel

 PLATFORM:

Windows 2000, XP, Server 2003

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

  • Threat Type: Worm

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Propagates via removable drives

This worm arrives by connecting affected removable drives to a system.

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

  TECHNICAL DETAILS

File Size:

558,742 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

27 Sep 2010

Payload:

Connects to URLs/Ips, Drops files

Arrival Details

This worm arrives by connecting affected removable drives to a system.

Installation

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

  • %System%\csrcs.exe

(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.)

It drops the following files:

  • %System%\autorun.i
  • %System%\autorun.in

(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\policies\
Explorer\Run
csrcs = %System%\csrcs.exe

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\RunServices
csrcs = %System%\csrcs.exe

It modifies the following registry entries to ensure it automatic execution at every system startup:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\Current Version\Winlogon
Shell = Explorer.exe csrcs.exe

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

Other System Modifications

This worm adds the following registry keys:

HKEY_LOCAL_MACHINE
@ =  

It modifies the following registry entries to hide files with Hidden attributes:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
Hidden = 2

(Note: The default value data of the said registry entry is 1.)

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
SuperHidden = 0

(Note: The default value data of the said registry entry is 1.)

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
ShowSuperHidden = 0

(Note: The default value data of the said registry entry is 1.)

Propagation

This worm drops copies of itself into all the removable drives connected to an affected system.

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

  • %System%\\csrcs.exe

(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.)

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

The said .INF file contains the following strings:

;{random}
[AutoRUN]
;{random}
SHeLL\OPeN\cOMmaND=GijlYc.exE
;{random}
OpEn=GIjlyC.exE
;{random}
iCON=%syStEm%\sHeLl32.dll,7
;{random}
UseauToplAy=1
;{random}
aCTioN=@gijlyc.exe
;{random}
Shell\oPen\DEFauLT=1
;{random}

Dropping Routine

This worm sets the attributes of its dropped file(s) to the following:

  • Hidden
  • Read-Only
  • System

Other Details

This worm connects to the following URL(s) to get the affected system's IP address:

  • http://www.whatismyip.com/automation/n09230945.asp

It does the following:

  • It also connects to the following URLs to get the affected system's country location:
  • http://{BLOCKED}c.daiguo.com/?self

  SOLUTION

Minimum Scan Engine:

8.900

VSAPI PATTERN File:

07.494.08

VSAPI PATTERN Date:

27 Sep 2010

VSAPI PATTERN Date:

9/27/2010 12:00:00 AM

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 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\policies\Explorer\Run
    • csrcs = %System%\csrcs.exe
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\RunServices
    • csrcs = %System%\csrcs.exe

Step 4

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. 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.

  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\DRM
    • amty

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\SOFTWARE\Microsoft\Windows NT\Current Version\Winlogon
    • From: Shell = Explorer.exe csrcs.exe
      To: Explorer.exe
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced
    • From: Hidden = 2
      To: 1
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced
    • From: SuperHidden = 0
      To: 1
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced
    • From: ShowSuperHidden = 0
      To: 1

Step 6

Search and delete AUTORUN.INF files created by WORM_UTOTI.JTB that contain these strings

[ Learn More ]
;{random}
[AutoRUN]
;{random}
SHeLL\OPeN\cOMmaND=GijlYc.exE
;{random}
OpEn=GIjlyC.exE
;{random}
iCON=%syStEm%\sHeLl32.dll,7
;{random}
UseauToplAy=1
;{random}
aCTioN=@gijlyc.exe
;{random}
Shell\oPen\DEFauLT=1
;{random}

Step 7

Search and delete this file

[ 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%\autorun.i
%System%\autorun.in

Step 8

Scan your computer with your Trend Micro product to delete files detected as WORM_UTOTI.JTB. 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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