Analysis by: Karl Dominguez
 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

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

  • Threat Type: Backdoor

  • Destructiveness: No

  • Encrypted: No

  • In the wild: Yes

  OVERVIEW

This backdoor is executed every system startup. In turn, it executes a file detected as BKDR_REDSIP.B. As a result, the malicious routines of said backdoor are also exhibited on the infected system.

This backdoor may arrive bundled with malware packages as a malware component. It may be dropped by other malware.

  TECHNICAL DETAILS

File Size: 49,152 bytes
File Type: PE
Initial Samples Received Date: 06 Jan 2011
Payload: Drops files

Arrival Details

This backdoor may arrive bundled with malware packages as a malware component.

It may be dropped by the following malware:

  • BKDR_REDSIP.B

NOTES:

This backdoor is dropped by BKDR_REDSIP.B into a system as %System%\Startup.dll.

This .DLL is executed every system startup by the service CryptHost which is created by BKDR_RESDIP.B:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\CryptHost
Type = 10
Start = 2
ErrorControl = 1
ImagePath = %System Root%\System32\svchost.exe -k CryptHost
ObjectName = LocalSystem

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\CryptHost\Parameters
ServiceDll = %System%\Startup.dll

It then executes %System%\Connect.dll, which is detected by Trend Micro as BKDR_REDSIP.B. As a result, malicious routines of the dropped backdoor are exhibited on the infected system.

  SOLUTION

Minimum Scan Engine: 8.900
FIRST VSAPI PATTERN FILE: 7.750.09
FIRST VSAPI PATTERN DATE: 06 Jan 2011
VSAPI OPR PATTERN File: 7.751.00
VSAPI OPR PATTERN Date: 11 Feb 2011

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

Remove malware files dropped/downloaded by BKDR_REDSIP.C

Step 3

Scan your computer with your Trend Micro product and note files detected as BKDR_REDSIP.C

Step 4

Search and delete the file detected as BKDR_REDSIP.C

[ Learn More ]
Please make sure you check the Search Hidden Files and Folders checkbox in the More advanced options option to include all hidden files in the search result.

Step 5

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.
%System%\Startup.dll


Did this description help? Tell us how we did.