Threat Description



Aliases: BZub.DN
Category: Malware
Type: Trojan-Spy
Platform: W32


BZub.DN, a variant of BZub, is a Trojan. BZub.DN creates files in the Windows directory and steals logins, passwords, PINs, check words and other info related to logging to bank websites.


Automatic action

Once detected, the F-Secure security product will automatically disinfect the suspect file by either deleting it or renaming it.


Detailed instructions for F-Secure security products are available in the documentation found in the Downloads section of our Home - Global site.

You may also refer to the Knowledge Base on the F-Secure Community site for further assistance.

Technical Details

The BZub.DN trojan was spammed to a large number of people as an attachment to an e-mail message. The attachment name was rechnung.exe, the same file name that was recently used for a spammed variant of Haxdoor backdoor. The trojan drops a keylogger and spies against users of several banks.After being run by the user, the trojan drops three files to the Window System folder. The dropped files represent the main spying component (ipv6monl.dll) and a keylogger (msn.exe and hook.dll). Both spying components are registered to start with every Windows session and remain active in memory at all times. The main spying component steals information related to various on-line banking accounts. Customers of the following banks and on-line payment systems may be affected:

  • Barklays
  • E-Gold
  • Intelligent Finance
  • Nationwide's Internet Bank
  • Postbank

The trojan also steals the following info and sends it to a hacker:

  • HTTP mail password
  • HTTP mail user name
  • IE autocomplete fields data
  • IE protected storage data
  • MSN Explorer signup data
  • Outlook account passwords
  • POP server name
  • POP server password
  • POP server user name
  • SMTP e-mail address

The keylogger records all keystrokes on an infected computer and sends the stolen info to the hacker.


Detection Type: PC
Database: 2006-09-12_09


Suspect a file or URL was wrongly detected? Submit a sample to our Labs for analysis

Submit Now

Give And Get Advice

Give advice. Get advice. Share the knowledge on our free discussion forum.

Learn More