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Troj/BankAsh-A

Aliases
  • Trojan-Spy.Win32.Banker.jv
  • PWS-Banker.j
Category
Type
What to do
Prevalence low high

Summary

 
Affected operating systems Windows
Characteristics
  • Drops more malware
Protection available since 9 February 2005 06:03:06 (GMT)
Last updated 2 January 2006 16:28:32 (GMT)
Detected by All Sophos products
  • Free virus, spyware, and adware scan
  • Test your existing anti-virus protection
  • Find threats your anti-virus missed

Action

Please follow the instructions for removing Trojans.

Change any data that may have become compromised.

You should also check your Internet Explorer settings using Tools|Internet options|General for any modifications made by the Trojan.

Replace the Hosts file from a backup or edit it in Notepad to remove the changes that the Trojan has made.

More Information

Troj/BankAsh-A is a banker and password stealing Trojan.

Troj/BankAsh-A will spy on a user's internet access. When certain banking and finance websites are accessed, the Trojan can display a fake login page or log keyboard presses in order to steal username and password information. Targeted banks include the following:

Barclays, Cahoot, Halifax, HSBC, Lloyds TSB, Nationwide, NatWest, Smile

The Trojan can also steal email login details and passwords from the protected store. Periodically, Troj/BankAsh-A will send the stolen details to a remote FTP site.

Troj/BankAsh-A will drop a DLL named ASH.DLL to the Windows system folder. This file is also detected as Troj/BankAsh-A. The Trojan will then register the DLL. Registry entries will be created under the following branches:

HKCR\CLSID\(C6176B04-8896-4446-9939-E00EE94C420F)
HKCR\AntiSpy.AntiSpy
HKCR\AntiSpy.AntiSpy.1

The DLL will register itself as an Interface, named "IIEHlprObj" and as a Type Library named "AS 0.96 Type Library". The following registry branches will be created:

HKCR\Interface\(17A45F93-AEC8-440B-AC33-1BA9CC3192AC)
HKCR\TypeLib\(D941DA88-1DAA-4ED2-8946-ABABCF2A4C3F)

Troj/BankAsh-A will modify Internet Explorer's Start page by setting the following registry entries:

HKCU\Software\Microsoft\Internet Explorer\Main
Start Page
about:blank

HKLM\SOFTWARE\Microsoft\Internet Explorer\Main
Start Page
about:blank

Troj/BankAsh-A will attempt to disable or kill the Microsoft AntiSpyware application. The Trojan will delete the following registry entry, if it exists:

HKLM\Software\Microsoft\Windows\CurrentVersion\Run\gcasServ

The Trojan will also attempt to terminate the following Microsoft AntiSpyware related processes:

GCASCLEANER
GCASDTSERV
GCASINSTALLHELPER
GCASNOTICE
GCASSERV
GCASSERVALERT
GCASSWUPDATER
GCIPTOHOSTQUEUE
GIANTANTISPYWAREMAIN
GIANTANTISPYWAREUPDATER

Troj/BankAsh-A will try to suppress warning messages that Microsoft AntiSpyware may display and will delete all files within the folder named "C:\Program Files\Microsoft AntiSpyware".

Troj/BankAsh-A may attempt to deny access to a number of websites by modifying the HOSTS file found in the Windows folder or the "%SYSTEM%\drivers\etc" folder.

Troj/BankAsh-A may download and run updates of itself.

Troj/BankAsh-A will attempt to unregister and delete a DLL named IEHELPER.DLL from the Windows system folder.

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