TROJ_DLOADR.RFV

April 16, 2014
 Analysis by: Adrian Cofreros
 ALIASES:

Win32/TrojanDownloader.Small.PSD trojan(NOD32),Trojan.Win32.Generic.pak!cobra(Sunbelt)

 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:
 INFORMATION EXPOSURE:

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

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

It executes the downloaded files. As a result, malicious routines of the downloaded files are exhibited on the affected system.

  TECHNICAL DETAILS

File Size:

89,600 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

09 Apr 2014

Arrival Details

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

Download Routine

This Trojan saves the files it downloads using the following names:

  • %User Temp%\mss{value}.exe
  • %Temporary Internet Files%\Content.IE5\{random}\{successful downloaded url file name}[1].txt - (example: %Temporary Internet Files%\Content.IE5\{random}\discreteness[1].txt)

(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.. %Temporary Internet Files% is the Temporary Internet Files folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temporary Internet Files on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Local\Microsoft\Windows\Temporary Internet Files on Windows Vista and 7.)

It then executes the downloaded files. As a result, malicious routines of the downloaded files are exhibited on the affected system.

Other Details

This Trojan connects to the following possibly malicious URL:

  • http://{BLOCKED}chanics.com/spengler/beatle
  • http://{BLOCKED}astersandiego.com/impugning/felsitic
  • http://{BLOCKED}universe.ca/bided/discreteness
  • http://{BLOCKED}.{BLOCKED}.161.78/mishapping/fleeceable
  • http://www.{BLOCKED}s.net/dyslexia/horizonless
  • http://{BLOCKED}60.co.uk/mervin/number
  • http://{BLOCKED}ttoplay.co.uk/duffer/salutations
  • http://{BLOCKED}icekitchencabinets.ca/abettor/unfloured
  • http://{BLOCKED}.{BLOCKED}.41.251/goiters/wonderless
  • http://{BLOCKED}tcollection.com/adverb/songless
  • http://www.{BLOCKED}boutiquehotelsandvillas.com/qualm/onder
  • http://{BLOCKED}-flooring.org.uk/stern/just
  • http://{BLOCKED}enta.co/mores/wait
  • http://{BLOCKED}temas.com.ar/ennobles/moment
  • http://{BLOCKED}o.com/carped/loose
  • http://{BLOCKED}ytours.ca/precluding/enlarge
  • http://www.{BLOCKED}decontracts.co.uk/racked/pennis
  • http://{BLOCKED}ndcommercials.co.uk/transepts/your
  • http://{BLOCKED}hofeck.de/gerardo/biggest
  • http://{BLOCKED}a.com.tr/pennons/fan
  • http://ftp.{BLOCKED}es.org/cajoling/make
  • http://{BLOCKED}s.co.za/willing/hill
  • http://{BLOCKED}lineuk.co.uk/habit/day
  • http://{BLOCKED}uialadivinamisericordia.com/starless/free
  • http://{BLOCKED}hofeck.de/motors/media
  • http://{BLOCKED}o.com/cruelly/wayder

  SOLUTION

Minimum Scan Engine:

9.700

FIRST VSAPI PATTERN FILE:

10.716.08

FIRST VSAPI PATTERN DATE:

09 Apr 2014

VSAPI OPR PATTERN File:

10.717.00

VSAPI OPR PATTERN Date:

10 Apr 2014

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.  
  • %User Temp%\mss{value}.exe

Step 3

Scan your computer with your Trend Micro product to delete files detected as TROJ_DLOADR.RFV. 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.

NOTES:

To delete %Temporary Internet Files%\Content.IE5\{random folder}\{successful downloaded url file name}[1].txt, do the following:

  1. Go to Start>Search.
  2. Click all files and folders and input the following information:
    All or part of the file name: {successful downloaded url file name}
    Look in %Temporary Internet Files%
  3. Once located, select the file then press SHIFT+DELETE.


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