PE_HUNK.NY

 Analysis by: Christopher Daniel So

 ALIASES:

Virus:Win32/Huhk.7005 (Microsoft), W32.Huhk.A (Symantec), W32/Huhk.c (McAfee), Worm.Win32.Huhk.c (Kaspersky), Win32.Huhc.B (FSecure), Worm.Win32.Huhk.c (Sunbelt)

 PLATFORM:

Windows 2000, XP, Server 2003

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

  • Threat Type: File infector

  • Destructiveness: No

  • Encrypted: No

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Infects files

This malware is a file infector that drops files.

It infects certain file types in the affected system.

  TECHNICAL DETAILS

File Size:

Varies

File Type:

PE

Memory Resident:

Yes

Initial Samples Received Date:

20 Jul 2008

Installation

This file infector drops the following files:

  • %User Temp%\lorer.exe - copy of the original %Windows%\explorer.exe

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

File Infection

This file infector infects the following files:

  • %Windows%\explorer.exe
  • %System%\dllcache\explorer.exe

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

It infects the following file types:

  • EXE

  SOLUTION

Minimum Scan Engine:

8.900

VSAPI OPR PATTERN File:

5.425.00

VSAPI OPR PATTERN Date:

22 Jul 2008

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

Identify and terminate files detected as PE_HUNK.NY

[ Learn More ]
  1. Windows Task Manager may not display all running processes. In this case, please use a third-party process viewer, preferably Process Explorer, to terminate the malware/grayware/spyware file. You may download the said tool here.
  2. If the detected file is displayed in either Windows Task Manager or Process Explorer but you cannot delete it, restart your computer in safe mode. To do this, refer to this link for the complete steps.
  3. If the detected file is not displayed in either Windows Task Manager or Process Explorer, continue doing the next steps.

Step 3

Restoring a File to its Original Location

  1. Click Start>Run.
  2. In the text box, type the following:
    command /c copy %User Temp%\lorer.exe %Windows%\explorer.exe
  3. Press Enter.

Step 4

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. %User Temp%\lorer.exe

Step 5

Scan your computer with your Trend Micro product to clean files detected as PE_HUNK.NY. 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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