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Category: Malware

Type: -

Aliases: Mocbot.A, Backdoor.Win32.Mocbot.a


Mocbot is an IRC bot that can spread using a vulnerability in Windows Plug and Play service (MS05-039).


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.

Knowledge Base

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About the product

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Contact Support

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Submit a sample

Submit a file or URL for further analysis.

Technical Details

Installation to system

The bot's file is a PE executable 7846 bytes long, packed with MEW file compressor.

When the bot's file is started, it copies itself as 'wudpcom.exe' file to Windows System folder and then creates a service with following attributes:

Service path: wudpcom.exe

Service name: Windows UDP Communication

Service short name: wudpcom

Description: Provides communication between clients and servers over UDP. If this service is stopped, UDP communication between clients and servers on the network will be impaired. If this service is disabled, any services that explicitly depend on it will fail to start.

Bot functionality

When the bot is active, it connects to an IRC server, joins a certain channel and acts as a bot there.

The following IRC servers are used by the bot:


The bot joins to password-protected IRC channel where the hacker can send commands to the bots to control infected computers. Several tasks can be performed, including the following:

 * perform SYN and UDP flood
* download and execute files
* start command shell
* scan and exploit computers vulnerable to MS05-039

Spreading using MS05-039

The bot scans for random IP addresses and exploits a vulnerability in Windows Plug and Play service (MS05-039).

Info on this PnP vulnerability is available here:


The vulnerability can be exploited via 139/TCP and 445/TCP.