Nessus Security Scanner Chosen as Best Open Source Tool of 2003 by PC Magazine.

Business Editors/High-Tech Writers

COLUMBIA, Md.--(BUSINESS WIRE)--Jan. 12, 2004

Tenable Network Security, Inc., a leading developer of security management solutions and primary sponsor for the open-source Nessus Security Scanner, announces that Nessus has been chosen as best open-source security tool for 2003 by PC Magazine.

"Nessus provides an astonishing quantity of customized tests called plug-ins. These include interesting scans that look for vulnerabilities in routers from Cisco and other companies, CGI scripts, buffer overruns, remote-access connections, back doors, RPC, and SNMP", says Oliver Kaven of PC Magazine. "Nessus will appeal most to administrators who want not only a comprehensive scanning tool but also an in-depth long-term education in network security vulnerabilities."

Founded in 2002 by the creator of the open-source Nessus security scanner and the creator of the Dragon intrusion detection system, Tenable continues to garner the attention of the Fortune 1000 companies that seek a simple, yet powerful approach to enterprise security management.

"I created Nessus to provide to the Internet community a free, powerful, up-to-date, and easy-to-use remote security scanner" says Renaud Deraison, Nessus creator and Tenable founder. "We founded Tenable to provide the enterprise community commercially supported security tools that not only leverage the performance of Nessus but also pass along the cost savings associated with using open source products."

Tenable's fully integrated product line includes:

Tenable's Lightning 2.0 (www.tenablesecurity.com/console.html) allows enterprises to dedicate Nessus/NeVO/NeWT Pro security scanners to distributed networks and manage security tasks and information from a web-based console. For enterprises that deploy Lightning, Tenable provides commercial support for the open-source Nessus scanners that are attached to Lightning. Lightning also provides many other enterprise features such as remediation work flow management, intrusion detection event aggregation and correlation and rich reporting.

Tenable's NeVO (www.tenablesecurity.com/nevo.html) is the industry's first "passive" vulnerability scanner. Deployed at network chokepoints, NeVO can give organizations 24 x 7 feedback on network vulnerabilities through network traffic analysis.

Tenable's NeWT and NeWT Pro (www.tenablesecurity.com/newt.html) are the commercial Windows versions of the widely popular Nessus open-source vulnerability scanner.

About Tenable Network Security, Inc.

Tenable provides security software which enables enterprises to distribute, manage, and communicate vulnerability and intrusion detection information across the entire organization. Detailed information can also be found on our website. http://www.tenablesecurity.com/.