TROJ_DELF.CEP

November 27, 2012
 ALIASES:

TrojanDownloader:Win32/Injector.gen!W (Microsoft); Generic Downloader.c (McAfee); Downloader (Symantec); Trojan-Downloader.Win32.Delf.ahr (Kaspersky); Trojan-Downloader.Win32.Small!cobra (v) (Sunbelt); Trojan.Generic.561744 (FSecure)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

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

  • 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.

  TECHNICAL DETAILS

File Size:

9,728 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

27 Nov 2012

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.

Other System Modifications

This Trojan modifies the following registry entries:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
DirectDraw\MostRecentApplication
Name = "IEXPLORE.EXE"

(Note: The default value data of the said registry entry is iexplore.exe.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
DirectDraw\MostRecentApplication
ID = "4117b81"

(Note: The default value data of the said registry entry is 41107b81.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
SystemCertificates\CA\Certificates\
8B24CD8D8B58C6DA72ACE097C7B1E3CEA4DC3DC6
Blob = "{random values}"

(Note: The default value data of the said registry entry is {random values}.)

Other Details

This Trojan connects to the following possibly malicious URL:

  • http://www.{BLOCKED}3.com/{random path}

This report is generated via an automated analysis system.

  SOLUTION

Minimum Scan Engine:

9.300

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

Restore these modified registry values

[ Learn More ]

Important:Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this only if you know how to or you can seek your system administrator's help. You may also check out this Microsoft article first before modifying your computer's registry.

  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\DirectDraw\MostRecentApplication
    • From: Name = "IEXPLORE.EXE"
      To: Name = ""iexplore.exe""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\DirectDraw\MostRecentApplication
    • From: ID = "4117b81"
      To: ID = ""41107b81""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\SystemCertificates\CA\Certificates\8B24CD8D8B58C6DA72ACE097C7B1E3CEA4DC3DC6
    • From: Blob = "{random values}"
      To: Blob = ""{random values}""

Step 3

Scan your computer with your Trend Micro product to delete files detected as TROJ_DELF.CEP. 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.