Feebs is a family of worms that spread using e-mail or P2P networks. Feebs usually comes as HTML application file (HTA) that installs the worm on infected system. Feebs hides itself using rootkit techniques.
Once detected, the F-Secure security product will automatically disinfect the suspect file by either deleting it or renaming it.
More information on the scanning and removal options available in your F-Secure product can be found in the Help Center.
You may also refer to the Knowledge Base on the F-Secure Community site for further assistance.
If the infection is in a local network, please follow the instructions on this webpage:
When the HTML application file (HTA) is opened, it drops the worm main executable file in 'C:\Command.exe' and executes it. The EXE file drops a file with single letter 'a'-'z' on C-drive and activates it. That file is the worm main DLL component. When active, it creates the following files:
The main DLL component also creates the following registry values for making sure the worm is activated on system startup:
Feebs can spread sending e-mail attachments containing the HTA dropper. The highly polymorphic HTA file is generated each time when the worm sends it. Feebs can also copy itself on shared folders used by some P2P applications.
Feebs starts HTTP server listening on port 80 for serving infected HTA files. The worm also starts server on random port which allows the attacker to control infected system. The random port is reported back to attacker using ICQ and HTTP. Feebs also tries to disable several security-related applications.
Feebs can hide its files, registry keys and network connections by utilizing rootkit techniques. The worm main DLL component is injected to all running processes and used for hooking the system library functions.