The malicious program, called Zlob, is capable of opening back-end ports on users' computers, hiding in files posted on Google's online video-sharing system.

When users click on a Zlob, it will attack their PC with a series of unwanted ads. Zlob can only last for a few hours but is enough to spread to a large number of computers because YouTube is a website with a record high number of hits.

The fake video recently discovered by Secure Computing (USA) titled " YouTube - Afterworld Episode 6 - Hibakusha ". Secure Computing expert Paul Henry said the file does not require people to download an .exe file, thus doubling the risk of the system being attacked.

Dangerous software on YouTube images 1 Also related to YouTube, Adobe last week introduced a video editing tool right on this video sharing website and MTV.com.

The free Adobe Premiere Express application allows people to edit images with a simple drag-and-drop operation to create files including video clips, music, photos, effects and titles .

Adobe Premiere Express works online, which means users do not need to download software to the computer but require the PC to support the Flash 9 tool.