BKDR_KIRPICH.D

 Analysis by: Mark Joseph Manahan

 ALIASES:

Trojan:Win32/Gyplit.A (Microsoft), Win32/Agent.THP trojan (Eset), Mal/Gyplit-A (Sophos), Trojan.Gen (Symantec)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

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

  • Threat Type: Backdoor

  • Destructiveness: No

  • Encrypted: Yes

  • 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:

39,936 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

13 Nov 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 files:

  • %Cookies%\winggf.dat
  • %User Profile%\Application Data\Adobe\Plugins\AcroRd32Info.exe
  • %Application Data%\Microsoft\Windows\Usrdpa.dat
  • %User Profile%\1.hiv
  • %User Profile%\2.hiv
  • %User Temp%\update.js

(Note: %User Profile% is the current user's profile folder, which is usually C:\Windows\Profiles\{user name} on Windows 98 and ME, C:\WINNT\Profiles\{user name} on Windows NT, and C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003.. %Application Data% is the current user's Application Data folder, which is usually C:\Windows\Profiles\{user name}\Application Data on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Application Data on Windows NT, and C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000, XP, and Server 2003.. %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.)

It creates the following folders:

  • %User Profile%\Application Data\Adobe\Plugins

(Note: %User Profile% is the current user's profile folder, which is usually C:\Windows\Profiles\{user name} on Windows 98 and ME, C:\WINNT\Profiles\{user name} on Windows NT, and C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003.)

Other System Modifications

This backdoor adds the following registry entries:

HKEY_CURRENT_USER\Microsoft\Windows\
CurrentVersion\Run
updater = "%User Profile%\Application Data\Adobe\Plugins\AcroRd32Info.exe"

Other Details

This backdoor connects to the following possibly malicious URL:

  • {BLOCKED}s.{BLOCKED}nline.us:80

  SOLUTION

Minimum Scan Engine:

9.300

FIRST VSAPI PATTERN FILE:

9.524.04

FIRST VSAPI PATTERN DATE:

13 Nov 2012

VSAPI OPR PATTERN File:

9.525.00

Step 1

For Windows XP and Windows Server 2003 users, before doing any scans, please make sure you disable System Restore to allow full scanning of your computer.

Step 2

Restart in Safe Mode

[ Learn More ]

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_CURRENT_USER\Microsoft\Windows\CurrentVersion\Run
    • updater = "%User Profile%\Application Data\Adobe\Plugins\AcroRd32Info.exe"

Step 4

Search and delete this file

[ Learn More ]
There may be some component 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.
  • %Cookies%\winggf.dat
  • %User Profile%\Application Data\Adobe\Plugins\AcroRd32Info.exe
  • %Application Data%\Microsoft\Windows\Usrdpa.dat
  • %User Profile%\1.hiv
  • %User Profile%\2.hiv
  • %User Temp%\update.js

Step 5

Restart in normal mode and scan your computer with your Trend Micro product for files detected as BKDR_KIRPICH.D. 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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