HTML_RANSOM.PPS

March 07, 2013
 Analysis by: Rhena Inocencio
 ALIASES:

Troj/Ransom-NY (Sophos)

 PLATFORM:

Windows 2000, Windows Server 2003, Windows XP (32-bit, 64-bit), Windows Vista (32-bit, 64-bit), Windows 7 (32-bit, 64-bit)

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Spammed via email

This Trojan arrives as an attachment to email messages spammed by other malware/grayware or malicious users.

  TECHNICAL DETAILS

File Size:

Varies

File Type:

HTA

Initial Samples Received Date:

06 Mar 3013

Payload:

Connects to URLs/IPs, Downloads files, Drops files

Arrival Details

This Trojan arrives as an attachment to email messages spammed by other malware/grayware or malicious users.

NOTES:

This Trojan checks if there is an installed Windows PowerShell on the system. If Windows Powershell is not installed, it downloads a copy from the following sites:

  • https://{BLOCKED}.{BLOCKED}x.com/sh/wn8x35r9l9wsitn/XSwafOFh9E/powershell.exe?dl=1

The downloaded file is saved as follows:

  • %User Temp%\powershell\powershell.exe

It drops the following file:

  • {Malware Path}\READ_ME_NOW.TXT

The file, READ_ME_NOW.TXT contains the following message:

When translated in English:

If you are reading this message, it means that your computer has been attacked by viruses.
All of your information (documents, movies, and other files) on the computer was encrypted
with the most cryptographically world RSA1024.
Restore files only through a special program. To obtain it, you need to
Go to go to a page on the Internet at http://bit.ly/11Uql6s and follow the instructions
If the link above does not work, go to a backup to http://{BLOCKED}k.{BLOCKED}p.to or http://{BLOCKED}t.ly/VIertW
When you try to decrypt the files without our software can be damaged!
DO NOT FORGET: Only we can decode your files!

As of this writing, the sites in READ_ME_NOW.TXT are inaccessible.

  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 files

[ 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.
  • {Malware Path}\READ_ME_NOW.TXT
  • %User Temp%\powershell\powershell.exe

Step 3

Scan your computer with your Trend Micro product to delete files detected as HTML_RANSOM.PPS. 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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