Cisco spokesman Jim Brady confirmed the launch of an investigation into the network breach but declined details on what was stolen.
"Cisco is aware that a potential compromise of its proprietary information occurred...Based on preliminary data, we don't believe any confidential customer information or financial systems were affected," he told internetnews.com
The Cisco response came after a Russian security Web site reported that hackers broke into the switching and routing giant's network and stole 800MB of source code for IOS 12.3 and 12.3t. Samples of the code were reportedly posted on an underground IRC channel as proof of the breach.
The company declined comment on the specifics of the breach until its security unit completes an investigation.
"It appears that this occurrence was not the result of any exploitation or a vulnerability of any product or service offered by Cisco," Brady said. "[We do not believe] it was the result of any malicious action by any Cisco employee or contractor."
Asked if news of the breach could put a damper on the company's well-documented integrated security push, Brady made it clear the network hack was not the result of a software or product flaw.