TROJ_DLOADR.AFG


 ALIASES:

Trojan.Gen (Symantec); Application/Downloader (Panda); Misc/OnlineInstaller (Fortinet)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: No

  • 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 accesses websites to download files. This action allows this malware to possibly add other malware on the affected computer.

  TECHNICAL DETAILS

File Size:

404,480 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

17 Aug 2011

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 files:

  • %User Temp%\is799009782\2112242300.cfg
  • %User Temp%\is799009782\662657193.cfg
  • %User Temp%\is799009782\999723057.cfg
  • %User Temp%\is799009782\{random numbers}_IronSourceCS.CIS

(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.)

It creates the following folders:

  • %User Temp%\is799009782

(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.)

Other System Modifications

This Trojan adds the following registry entries:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Internet Explorer\AboutURLs
Tabs = "http://gg.blogpear.com/vscript/newTB.psc?&ub=_%7c0U0I0DzutDtDtD0CtBzyyCzztCyB0C0CtN0P1C0S1Czu0M0D0P0LtN0C0H0Nzu0S0R0C0Hzx0N1P2W0T0BtN0B0N0Dzu0B0B0N1VtCtAtDyDyEtN0C0Dzu0P0R0EtN0L0N0Tzu%7c_&cr=54398338"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\Shar dAccess\Parameters\
FirewallPolicy\StandardProfile\AuthorizedApplications\
List
{malware path and filename} = "{malware path and filename}:*:Enabled:Media Player"

It adds the following registry keys as part of its installation routine:

HKEY_LOCAL_MACHINE\SOFTWARE\Awsdata

Download Routine

This Trojan accesses websites to download the following files:

  • http://{BLOCKED}d.{BLOCKED}ta.com/Bund/AInstaller.CIS
  • http://{BLOCKED}d.{BLOCKED}a.com/Prod/vlc-8.0.5.CIS
  • http://{BLOCKED}v.{BLOCKED}er.org/vscript/utils/IP2CC.psc
  • http://{BLOCKED}d.{BLOCKED}a.com/Bund/Babylon/Babylon8_sq_14542.cis

  SOLUTION

Minimum Scan Engine:

8.900

FIRST VSAPI PATTERN FILE:

8.358.15

FIRST VSAPI PATTERN DATE:

17 Aug 2011

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

Identify and terminate files detected as TROJ_DLOADR.AFG

[ Learn More ]
  1. Windows Task Manager may not display all running processes. In this case, please use a third-party process viewer, preferably Process Explorer, to terminate the malware/grayware/spyware file. You may download the said tool here.
  2. If the detected file is displayed in either Windows Task Manager or Process Explorer but you cannot delete it, restart your computer in safe mode. To do this, refer to this link for the complete steps.
  3. If the detected file is not displayed in either Windows Task Manager or Process Explorer, continue doing the next steps.

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\SOFTWARE\Microsoft\Internet Explorer\AboutURLs
    • Tabs = "http://gg.blogpear.com/vscript/newTB.psc?&ub=_%7c0U0I0DzutDtDtD0CtBzyyCzztCyB0C0CtN0P1C0S1Czu0M0D0P0LtN0C0H0Nzu0S0R0C0Hzx0N1P2W0T0BtN0B0N0Dzu0B0B0N1VtCtAtDyDyEtN0C0Dzu0P0R0EtN0L0N0Tzu%7c_&cr=54398338"
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Shar dAccess\Parameters\FirewallPolicy\StandardProfile\AuthorizedApplications\List
    • {malware path and filename} = "{malware path and filename}:*:Enabled:Media Player"

Step 4

Delete this registry key

[ 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. Before you could do this, you must restart in Safe Mode. For instructions on how to do this, you may refer to this page If the preceding step requires you to restart in safe mode, you may proceed to edit the system registry.

  • In HKEY_LOCAL_MACHINE\SOFTWARE
    • Awsdata

Step 5

Search and delete this folder

[ Learn More ]
Please make sure you check the Search Hidden Files and Folders checkbox in the More advanced options option to include all hidden folders in the search result.
  •  %User Temp%\is799009782

Step 6

Scan your computer with your Trend Micro product to delete files detected as TROJ_DLOADR.AFG. 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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