Additional Details
There are some reports from customers that BZub.BS arrives via spam mail. See the screenshot below:
This malware has two components:
- Spammed file - Rakningen.exe (Installer)
- Ipv6mons.dll (Contains malicious routines and is injected in Internet Explorer)
Upon the execution of Rakningen.exe, it will install its .dll component by dropping the file Ipv6mons.dll into the Windows Systems Directory. It adds several encrypted or random registry values under the following subkey as its auto start technique:
- [SOFTWARE\Microsoft\Windows\CurrentVersion\Control Panel\load]
The registry values are the following:
- cmpid
- forwas
- h
- net_insll
- nw
- worg
- wspopp
Moreover, it registers itself as a Browser Helper Object (BHO) using the following registry entries:
- [HKEY_CLASSES_ROOT\CLSID\\InprocServer32]
@ = "{systemdir}\ipv6mons.dll"
- [HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\\InprocServer32]
@ = "{systemdir}\ipv6mons.dll"
It also registers its Internet Explorer as an authorized application to prevent the Windows Firewall from blocking network transactions through the said program:
- [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SharedAccess
\Parameters\FirewallPolicy\StandardProfile\AuthorizedApplications\List]
" {Program Files}\Internet Explorer\IEXPLORE.EXE" = " {Program Files} \Internet Explorer\IEXPLORE.EXE:*:Enabled:Internet Explorer"
BZub.BS also makes a copy of the existing file C:\lofg.xxx to C:\ewerufeassur8fr.
It deletes the following files:
- C:\clearsdingdrfive
- C:\test.txt
BZub.BS connects to the following FTP site:
Creates a file named info.txt containing information about the infected system:
- Computer ID
- Computer name
- Country/Region
- IP Address
- Windows version
Steals information about the following by monitoring websites/forms and querying some registries:
- Bank logon details
- Cache password
- Hotmail smtp/pop3 server
- IEAutoCompleteFields
- MSN Explorer Signup
- Outlook Express
The malware steals logon details to banks that have the following strings:
- app/ueberweisung.input.do
- app/ueberweisung.prep.do
- banking.postbank.de
- banking.postbank.de/app/finanzstatus.reduziert.init.do
- banking.postbank.de/app/kontoumsatz.umsatz.init.do
- banking.postbank.de/app/legitimation.input.do
- banking.postbank.de/app/ueberweisung.quittung.do
- e-gold.com/acct/acct.asp
- https://*.netbank.commbank.com.au/netbank/bankmain
- https://banking.postbank.de/app/finanzstatus.init.do
- https://banking.postbank.de/app/kontoumsatz.umsatz.init.do
- https://banking.postbank.de/app/welcome.do
- https://signin.ebay*/ws/eBayISAPI.dll
- postbank.de
This malware sends gathered information via FTP using any of the following files:
- form.txt
- info.txt
- shot.txt