PE_POREX.A

July 01, 2013
 ALIASES:

Virus:Win32/Porex.B (Microsoft); W32/Porex !! (McAfee); W32.Porex (Symantec); Virus.Win32.Porex.b (Kaspersky); Virus.Win32.Porex.b (v) (Sunbelt); Win32/Porex.B (AVG)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

 OVERALL RISK RATING:
 REPORTED INFECTION:

  • Threat Type: File infector

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

This file infector 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:

66,656 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

09 May 2013

Arrival Details

This file infector arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

Other System Modifications

This file infector deletes the following files:

  • {malware path and file name}.exe
  • %User Profile%\{AC76BA86-7AD7-1033-7B44-AA0000000001}\setup.exe

(Note: %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003, or C:\Users\{user name} on Windows Vista and 7.)

Dropping Routine

This file infector drops the following files:

  • %User Temp%\TMPTMP.$11
  • %User Temp%\TMP$$001.TMP
  • %Windows%\poserv.exe
  • Y:\TMPTMP.$11
  • X:\TMPTMP.$11
  • W:\TMPTMP.$11
  • V:\TMPTMP.$11
  • U:\TMPTMP.$11
  • T:\TMPTMP.$11
  • S:\TMPTMP.$11
  • R:\TMPTMP.$11
  • Q:\TMPTMP.$11
  • P:\TMPTMP.$11
  • O:\TMPTMP.$11
  • N:\TMPTMP.$11
  • M:\TMPTMP.$11
  • L:\TMPTMP.$11
  • K:\TMPTMP.$11
  • J:\TMPTMP.$11
  • I:\TMPTMP.$11
  • H:\TMPTMP.$11
  • G:\TMPTMP.$11
  • F:\TMPTMP.$11
  • E:\TMPTMP.$11
  • D:\TMPTMP.$11
  • %System Root%\TMPTMP.$11
  • %Temp%\TMPTMP.$11
  • %Temp%\TMP$$001.TMP

(Note: %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Local\Temp on Windows Vista and 7.. %Windows% is the Windows folder, which is usually C:\Windows.. %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.. %Temp% is the Windows Temporary folder, which is usually C:\Windows\Temp.)

This report is generated via an automated analysis system.

  SOLUTION

Minimum Scan Engine:

9.300

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

Search and delete these components

[ Learn More ]
There may be some components 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%\TMPTMP.$11
  • %User Temp%\TMP001.TMP
  • %Windows%\poserv.exe
  • Y:\TMPTMP.$11
  • X:\TMPTMP.$11
  • W:\TMPTMP.$11
  • V:\TMPTMP.$11
  • U:\TMPTMP.$11
  • T:\TMPTMP.$11
  • S:\TMPTMP.$11
  • R:\TMPTMP.$11
  • Q:\TMPTMP.$11
  • P:\TMPTMP.$11
  • O:\TMPTMP.$11
  • N:\TMPTMP.$11
  • M:\TMPTMP.$11
  • L:\TMPTMP.$11
  • K:\TMPTMP.$11
  • J:\TMPTMP.$11
  • I:\TMPTMP.$11
  • H:\TMPTMP.$11
  • G:\TMPTMP.$11
  • F:\TMPTMP.$11
  • E:\TMPTMP.$11
  • D:\TMPTMP.$11
  • %System Root%\TMPTMP.$11
  • %Temp%\TMPTMP.$11
  • %Temp%\TMP001.TMP
001.TMP
  • %Windows%\poserv.exe
  • Y:\TMPTMP.$11
  • X:\TMPTMP.$11
  • W:\TMPTMP.$11
  • V:\TMPTMP.$11
  • U:\TMPTMP.$11
  • T:\TMPTMP.$11
  • S:\TMPTMP.$11
  • R:\TMPTMP.$11
  • Q:\TMPTMP.$11
  • P:\TMPTMP.$11
  • O:\TMPTMP.$11
  • N:\TMPTMP.$11
  • M:\TMPTMP.$11
  • L:\TMPTMP.$11
  • K:\TMPTMP.$11
  • J:\TMPTMP.$11
  • I:\TMPTMP.$11
  • H:\TMPTMP.$11
  • G:\TMPTMP.$11
  • F:\TMPTMP.$11
  • E:\TMPTMP.$11
  • D:\TMPTMP.$11
  • %System Root%\TMPTMP.$11
  • %Temp%\TMPTMP.$11
  • %Temp%\TMP001.TMP
    •
  • In the Look In drop-down list, select My Computer then press Enter.
  • Once located, select the file then press SHIFT+DELETE to delete it.
  • Repeat the said steps for all files listed.

    • • For Windows Vista and Windows 7 users:

    1. Click Start>Computer.
    2. In the Search input box, type:
      • %User Temp%\TMPTMP.$11
      • %User Temp%\TMP001.TMP
      • %Windows%\poserv.exe
      • Y:\TMPTMP.$11
      • X:\TMPTMP.$11
      • W:\TMPTMP.$11
      • V:\TMPTMP.$11
      • U:\TMPTMP.$11
      • T:\TMPTMP.$11
      • S:\TMPTMP.$11
      • R:\TMPTMP.$11
      • Q:\TMPTMP.$11
      • P:\TMPTMP.$11
      • O:\TMPTMP.$11
      • N:\TMPTMP.$11
      • M:\TMPTMP.$11
      • L:\TMPTMP.$11
      • K:\TMPTMP.$11
      • J:\TMPTMP.$11
      • I:\TMPTMP.$11
      • H:\TMPTMP.$11
      • G:\TMPTMP.$11
      • F:\TMPTMP.$11
      • E:\TMPTMP.$11
      • D:\TMPTMP.$11
      • %System Root%\TMPTMP.$11
      • %Temp%\TMPTMP.$11
      • %Temp%\TMP001.TMP
    3. Once located, select the file then press SHIFT+DELETE to delete it.
    4. Repeat the said steps for all files listed.
      *Note: Read the following Microsoft page if these steps do not work on Windows 7.

    Step 3

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

    Step 4

    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.

    • {malware path and file name}.exe
    • %User Profile%\{AC76BA86-7AD7-1033-7B44-AA0000000001}\setup.exe


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