TROJ_UPATRE.DA

May 12, 2015
 Modified by: Jimelle Monteser
 ALIASES:

Win32/TrojanDownloader.Small.AAB trojan (NOD32)

 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.

It deletes the initially executed copy of itself.

  TECHNICAL DETAILS

File Size:

20,480 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

21 Nov 2013

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.

Installation

This Trojan drops the following copies of itself into the affected system and executes them:

  • %User Temp%\budha.exe

(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)

Download Routine

This Trojan downloads the file from the following URL and renames the file when stored in the affected system:

  • {BLOCKED}plive.com/upload/html.exe
  • {BLOCKED}e.com/knowledge/misc/html.exe
  • {BLOCKED}plive.com/upload/html.exe

It saves the files it downloads using the following names:

  • %User Temp%\kilf.exe
  • %Temporary Internet Files%\Content.IE5\{random folder name}\html[1].exe

(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.. %Temporary Internet Files% is the Temporary Internet Files folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temporary Internet Files on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Microsoft\Windows\Temporary Internet Files on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), and Windows Server 2008; C:\Users\{user name}\AppData\Local\Microsoft\Windows\INetCache on Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), and Windows Server 2012.)

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 deletes the initially executed copy of itself

  SOLUTION

Minimum Scan Engine:

9.700

FIRST VSAPI PATTERN FILE:

10.422.08

FIRST VSAPI PATTERN DATE:

21 Nov 2013

VSAPI OPR PATTERN File:

10.423.00

VSAPI OPR PATTERN Date:

21 Nov 2013

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 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%\kilf.exe

Step 3

Scan your computer with your Trend Micro product to delete files detected as TROJ_UPATRE.DA. 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}\html[1].exe:

  1. Go to Start
  2. Search
  3. Click All files and folders and input the following information:

    All or part of the file name html[1].exe
    Look in %Temporary Internet Files%\Content.IE5
  4. Once located, select the file then press SHIFT+DELETE to permanently delete the file.


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