ALIASES:

TrojanDownloader:Win32/Pangu.A (Microsoft); Downloader.a!bbl (McAfee); Infostealer.Gampass (Symantec); Backdoor.Win32.Small.hpm (Kaspersky); BehavesLike.Win32.Malware.spi (mx-v) (Sunbelt); Gen:Trojan.Agent.Delf.GY.dqX@aOLJm7hb (FSecure)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

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

  • Threat Type: Backdoor

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

This backdoor 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: 61,113 bytes
File Type: EXE
Memory Resident: No
Initial Samples Received Date: 31 Dec 2012

Arrival Details

This backdoor 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 backdoor drops the following copies of itself into the affected system:

  • %System%\{malware file name}.exe

(Note: %System% is the Windows system folder, which is usually C:\Windows\System32.)

Other System Modifications

This backdoor adds the following registry entries:

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\snake_service_svcname
Description = "snake_service_display"

Dropping Routine

This backdoor drops the following files:

  • %User Temp%\~sNiu.tmp
  • %System%\drivers\ApiHooks.sys
  • %Temp%\~sNiu.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.. %System% is the Windows system folder, which is usually C:\Windows\System32.. %Temp% is the Windows Temporary folder, which is usually C:\Windows\Temp.)

Other Details

This backdoor connects to the following possibly malicious URL:

  • http://www.{BLOCKED}s.com/ssdt/Dlbest.exe
  • http://snakeddos.{BLOCKED}2.org/1.exe

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

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\ControlSet001\Services\snake_service_svcname
    • Description = "snake_service_display"

Step 3

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%\~sNiu.tmp
  • %System%\drivers\ApiHooks.sys
  • %Temp%\~sNiu.tmp

Step 4

Scan your computer with your Trend Micro product to delete files detected as BKDR_EPROT.AL. 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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