WORM_PALEVO.CJ

 Analysis by: Cris Nowell Pantanilla

 PLATFORM:

Windows 2000, XP, Server 2003

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

  • Threat Type: Worm

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Propagates via removable drives


However, as of this writing, the said sites are inaccessible.

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.

It connects to certain URLs. It may do this to remotely inform a malicious user of its installation. It may also do this to download possibly malicious files onto the computer, which puts the computer at a greater risk of infection by other threats.

  TECHNICAL DETAILS

File Size:

Varies

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

01 Oct 2010

Payload:

Connects to URLs/Ips

Arrival Details

However, as of this writing, the said sites are inaccessible.

Installation

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

  • %Application Data%\ydze.exe

(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Windows\Profiles\{user name}\Application Data on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Application Data on Windows NT, and C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000, XP, and Server 2003.)

It injects itself into the following processes running in the affected system's memory:

  • EXPLORER.EXE

Autostart Technique

This worm adds the following registry entries to enable its automatic execution at every system startup:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Winlogon
Taskman = %Application Data%\ydze.exe

Propagation

This worm creates the following folders in all removable drives:

  • Kick,Ass.2010

It 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:

  • {Drive:}\Kick,Ass.2010\Kick.Ass.2010.R5.XviD-triniwarez.com.exe

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:

{garbage}
[AutoRun]
{garbage}
OPEN=Kick,Ass.2010//Kick.Ass.2010.R5.XviD-triniwarez.com.exe
{garbage}
UstAutoplay=1
{garbage}
Shell\EXplore\COMMAND=Kick,Ass.2010\Kick.Ass.2010.R5.XviD-triniwarez.com.exe
{garbage}
Shell\OPEN\COMMAND=Kick,Ass.2010//\Kick.Ass.2010.R5.XviD-triniwarez.com.exe
{garbage}

Download Routine

This worm connects to the following malicious URLs:

  • {BLOCKED}bam.info
  • {BLOCKED}rystorm.net
  • {BLOCKED}ucks.com

  SOLUTION

Minimum Scan Engine:

8.900

VSAPI PATTERN File:

07.506.01

VSAPI PATTERN Date:

01 Oct 2010

VSAPI PATTERN Date:

10/1/2010 12:00:00 AM

Step 1

Scan your computer with your Trend Micro product and note files detected as WORM_PALEVO.CJ

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 NT\CurrentVersion\Winlogon
    • Taskman=%Application Data%\ydze.exe

Step 4

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.
  • %Application Data%\ydze.exe

Step 5

Search and delete these folders

[ 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.
  • Kick,Ass.2010

Step 6

Search and delete AUTORUN.INF files created by WORM_PALEVO.CJ that contain these strings

[ Learn More ]
{garbage}
[AutoRun]
{garbage}
OPEN=Kick,Ass.2010//Kick.Ass.2010.R5.XviD-triniwarez.com.exe
{garbage}
UstAutoplay=1
{garbage}
Shell\EXplore\COMMAND=Kick,Ass.2010\Kick.Ass.2010.R5.XviD-triniwarez.com.exe
{garbage}
Shell\OPEN\COMMAND=Kick,Ass.2010//\Kick.Ass.2010.R5.XviD-triniwarez.com.exe
{garbage}

Step 7

Scan your computer with your Trend Micro product to delete files detected as WORM_PALEVO.CJ. 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.


Did this description help? Tell us how we did.