Some of the source code from one of Kaspersky Labs' antivirus products has been posted on the Internet.

According to the Russian news publication CNews (Google translation), the source code of Kaspersky Internet Security was posted at a free file hosting site, Mlfat4arab.

Kaspersky told CNews that the code contained "a fragment of an older version of the antivirus engine, which had previously been circulated in closed hacking resources."

As of Friday, the source code had been downloaded more than 2,000 times, according to the report. The archive contains a collection of files with code written using a C ++ tool in Visual C, as well as assembly files, CNews says.

"Judging by the names of the folders in the archive, it contains the source code of the engine KLAVA, which is a work [which] entered the final phase in 2008," the report says.

Researchers who investigated the code say it was released by a disgruntled developer and has been for sale for some time, with no apparent takers.

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