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Backdoor:W32/Bifrose.EE

Classification

Category: Malware

Type: Backdoor

Aliases: Bifrose.EE, Bifrose, Backdoor.Win32.Bifrose.ee

Summary


Bifrose is a stealthy backdoor that allows remote access to infected machine. It is usually installed to system by a trojan dropper.

Removal


Automatic action

Based on the settings of your F-Secure security product, it will either automatically delete, quarantine or rename the detected program or file, or ask you for a desired action.

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Submit a sample

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Technical Details


Installation to system

When run, the backdoor copies itself under %SysDir% directory using the name 'syspare.exe'. It installs the following registry keys to make sure it will be executed next time the system is started:

[HKLM\Software\Microsoft\Windows\CurrentVersion\Run]
"syspare.exe" = "syspare.exe"
[HKLM\Software\Microsoft\Active Setup\Installed Components\{9B71D88C-C598-4935-C5D1-43AA4DB90836}]
"stubpath.exe" = "syspare.exe"
 

The backdoor also creates the following registry key for storing information:

[HKLM\Software\Wget]
Backdoor

After the installation, Bifrose tries to locate a running web browser and inject code into it. The injected code is the actual backdoor. The backdoor starts to communicate with the server part using specially crafted HTTP queries. The server can instruct the backdoor to execute the following actions:

Basic file operations (copy, delete, rename, find, execute)
Download/upload files
Process operations (list, kill)
Registry operations (create/delete keys/values)
Create screenshots of the desktop