The Softpedia newswire asserts that the source code dates back to late 2007/early 2008 and has been written in C++ and Delphi.
The newswire notes that the source codes covers the anti-virus engine, as well as the anti-phishing, anti-dialer, anti-spam, parental control, and other IT security modules.
"We don't know yet to what version of Kaspersky's security suite the sources actually correspond to, but 8.0 is the most likely candidate at this point", says the newswire.
"We have contacted the company at several different email addresses to ask for clarifications regarding this major intellectual property theft incident, but we have yet to receive a response", it adds.
Infosecurity notes that rumours surrounding the source code on Kaspersky AV being for sale were circulating in the spring of 2009 and, as Lucian Constantin says in his story, it has been suggested that the hackers responsible originally put the code up for sale.
The CNews newswire in Russia, meanwhile, says that code leak stems from a Kaspersky employee who stolen the source code in the early part of 2008.
Despite reports that the source code is outdated, Infosecurity notes that developers from competing IT security companies have expressed great interest in the files.