Analysis by: RonJay Kristoffer Caragay
ALIASES:

Trojan-Downloader.Win32.Upatre.ajuu (Kaspersky), TrojanDownloader:Win32/Upatre (Microsoft)

 PLATFORM:

Windows

 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 deletes the initially executed copy of itself.

  TECHNICAL DETAILS

File Size: 143,360 bytes
Memory Resident: No

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%\nyupodyt.exe
  • %User Temp%\Opesnica.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.)

It drops the following files:

  • %User Temp%\~DR7892.txt
  • %User Temp%\OpnesLog.tmp
  • %User Temp%\{random filename}.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.)

Other System Modifications

This Trojan adds the following registry entries:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile
EnableFirewall = "0"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile
DoNotAllowExceptions = "0"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile
DisableNotifications = "1"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
services\SharedAccess\Parameters\
FirewallPolicy\PublicProfile
EnableFirewall = "0"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
services\SharedAccess\Parameters\
FirewallPolicy\PublicProfile
DoNotAllowExceptions = "0"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
services\SharedAccess\Parameters\
FirewallPolicy\PublicProfile
DisableNotifications = "1"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
services\SharedAccess\Parameters\
FirewallPolicy\DomainProfile
EnableFirewall = "0"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
services\SharedAccess\Parameters\
FirewallPolicy\DomainProfile
DoNotAllowExceptions = "0"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
services\SharedAccess\Parameters\
FirewallPolicy\DomainProfile
DisableNotifications = "1"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
services\SharedAccess
Start = "4"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Security Center
AntiVirusDisableNotify = "1"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Security Center
AntiVirusOverride = "1"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Security Center
FirewallDisableNotify = "1"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Security Center
FirewallOverride = "1"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Security Center
UpdatesDisableNotify = "1"

Other Details

This Trojan connects to the following possibly malicious URL:

  • http://{BLOCKED}.{BLOCKED}.4.90:{port}/KTA12/{Host Name}
  • http://{BLOCKED}.{BLOCKED}.4.90:{port}/SKS12/{Host Name}
  • https://{BLOCKED}.{BLOCKED}.123.66/soks12.png
  • https://{BLOCKED}.{BLOCKED}.232.219/soks12.png
  • https://{BLOCKED}.{BLOCKED}.226.85/soks12.png
  • https://{BLOCKED}.{BLOCKED}.126.8/soks12.png
  • https://{BLOCKED}.{BLOCKED}.240.56/soks12.png
  • https://{BLOCKED}.{BLOCKED}.255.79/kisty12.pdf
  • https://{BLOCKED}.{BLOCKED}.16.79/kisty12.pdf
  • https://{BLOCKED}.{BLOCKED}.20.145/kisty12.pdf
  • https://{BLOCKED}.{BLOCKED}.22.227/kisty12.pdf
  • https://{BLOCKED}.{BLOCKED}.27.163/kisty12.pdf
  • https://{BLOCKED}.{BLOCKED}.29.213/kisty12.pdf
  • https://{BLOCKED}.{BLOCKED}.29.43/soks12.png
  • https://{BLOCKED}.{BLOCKED}.31.1/kisty12.pdf
  • https://{BLOCKED}.{BLOCKED}.31.6/kisty12.pdf
  • https://{BLOCKED}.{BLOCKED}.251.208/soks12.png
  • https://{BLOCKED}.{BLOCKED}.221.89/kisty12.pdf
  • https://{BLOCKED}.{BLOCKED}.34.130/soks12.png
  • https://{BLOCKED}.{BLOCKED}.134.177/soks12.png
  • https://{BLOCKED}.{BLOCKED}.142.250/kisty12.pdf
  • https://{BLOCKED}.{BLOCKED}.165.154/soks12.png
  • https://{BLOCKED}.{BLOCKED}.241.59/soks12.png
  • https://{BLOCKED}.{BLOCKED}.153.153/soks12.png
  • https://{BLOCKED}.{BLOCKED}.92.193/soks12.png
  • https://{BLOCKED}.{BLOCKED}.107.12/kisty12.pdf
  • https://{BLOCKED}.{BLOCKED}.144.177/kisty12.pdf
  • https://{BLOCKED}.{BLOCKED}.72.224/kisty12.pdf
  • https://{BLOCKED}.{BLOCKED}.38.186/soks12.png
  • https://{BLOCKED}.{BLOCKED}.121.6/soks12.png
  • https://{BLOCKED}.{BLOCKED}.204.114/kisty12.pdf
  • https://{BLOCKED}.{BLOCKED}.203.173/kisty12.pdf

It deletes the initially executed copy of itself

  SOLUTION

Minimum Scan Engine: 9.750
FIRST VSAPI PATTERN FILE: 11.682.07
FIRST VSAPI PATTERN DATE: 21 May 2015
VSAPI OPR PATTERN File: 11.683.00
VSAPI OPR PATTERN Date: 21 May 2015

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

Note that not all files, folders, and registry keys and entries are installed on your computer during this malware's/spyware's/grayware's execution. This may be due to incomplete installation or other operating system conditions. If you do not find the same files/folders/registry information, please proceed to the next step.

Step 3

Delete this registry value

[ Learn More ]

Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.

 
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\SharedAccess\Parameters\FirewallPolicy\StandardProfile
    • EnableFirewall = "0"
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\SharedAccess\Parameters\FirewallPolicy\StandardProfile
    • DoNotAllowExceptions = "0"
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\SharedAccess\Parameters\FirewallPolicy\StandardProfile
    • DisableNotifications = "1"
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\SharedAccess\Parameters\FirewallPolicy\PublicProfile
    • EnableFirewall = "0"
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\SharedAccess\Parameters\FirewallPolicy\PublicProfile
    • DoNotAllowExceptions = "0"
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\SharedAccess\Parameters\FirewallPolicy\PublicProfile
    • DisableNotifications = "1"
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\SharedAccess\Parameters\FirewallPolicy\DomainProfile
    • EnableFirewall = "0"
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\SharedAccess\Parameters\FirewallPolicy\DomainProfile
    • DoNotAllowExceptions = "0"
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\SharedAccess\Parameters\FirewallPolicy\DomainProfile
    • DisableNotifications = "1"
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\SharedAccess
    • Start = "4"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Security Center
    • AntiVirusDisableNotify = "1"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Security Center
    • AntiVirusOverride = "1"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Security Center
    • FirewallDisableNotify = "1"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Security Center
    • FirewallOverride = "1"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Security Center
    • UpdatesDisableNotify = "1"

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%\~DR7892.txt
  • %User Temp%\OpnesLog.tmp
  • %User Temp%\{random filename}.exe

Step 5

Scan your computer with your Trend Micro product to delete files detected as TROJ_UPATRE.SM24. 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.


Did this description help? Tell us how we did.