Cisco’s Code Posted on Russian Website

Cisco Systems Inc., the largest maker of computers that link networks, said Monday that some of its software code that helps run the Internet was posted to a Russian website, and may have been stolen.

Programming instructions that make up the operating system software running San Jose-based Cisco’s computer equipment were posted last week, spokeswoman Mojgan Khalili said. She declined to say when Cisco became aware of the posting, but said the company was investigating.

“Cisco is aware that a potential compromise of its proprietary information occurred and was reported on a public website,” Khalili said. Hyperlinks on the website led to Web pages displaying software instructions and a Cisco copyright.

Cisco would not say whether or how much of its code may have been stolen.

Source code, the underlying blueprint of computer software, determines how programs work. Companies such as Cisco and Microsoft Corp. zealously guard their source code because they consider it the lifeblood of their business. Source code also could let hackers learn how a computer program works and how to manipulate it. The U.S. Department of Homeland Security on April 21 warned that a flaw in Cisco’s Internet Operating System software may let hackers knock out company machines that run the Internet.

The posting of Cisco code follows a posting on the Internet in February of instructions from Microsoft’s Windows operating system software, which runs 93% of the world’s personal computers.

Numerous versions exist of Cisco’s Internetworking Operating System, which means that the suspected theft may not affect all of its gear.

Shares of Cisco fell 31 cents to $20.93 on Nasdaq.

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Bloomberg News and Reuters were used in compiling this report.