Hidden malware search capabilities within Google which were reserved for antivirus and security research firms just weeks ago have been cracked by hackers, according to security industry sources.

The key to finding malware in Google lies in having the signature for the specific malware program, according to researchers from enterprise IT security firm Secure Computing.

However, the company reported that these previously hidden search capabilities have recently fallen into the hands of hackers.

"Why bother creating a new virus, worm or Trojan when you can simply find one and download it using Google?" said Paul Henry, vice president of strategic accounts at Secure Computing.

"Unskilled hackers can use this previously unknown capability of Google to download malware and release it on the internet in targeted attacks as if they wrote it themselves."

Secure Computing said that hackers are now sharing these signatures openly on the internet, making it easy to search Google for the signature of a specific piece of malware.

Websites now catalogue these signatures and allow users simply to enter the malware program name and download the signature for the malware from the database, Henry warned.

Users of these signature catalogues are encouraged to submit new malware so that the site owners can quickly generate a signature for the malware for their community of users.