SAN FRANCISCO -- RSA Conference 2010 -- Matasano Security here today rolled out a new Web-based open-source tool that scans for any firewall rules that are outdated, redundant, or could potentially expose a network to security threats.

"Flint makes sure nothing in [your firewall changes and configurations] creates a security problem," says Tom Ptacek, principal with Matasano, a security consulting and research firm.

Ptacek says compliance requirements -- namely PCI -- and secure software development efforts are forcing organizations to take a closer look at their firewall configurations. "They are starting to take their internal apps a lot more seriously ... as they review their apps, they have a review associated with firewall configurations," Ptacek says. "Apps get retired and get new revs. As part of their assessments, they are going back to the firewall rules that let those apps run."

Flint is the second product offering from Matasano: Its first product, Playbook, is a VMWare-based virtual appliance that centralizes and synchronizes the control and management of multiple vendors' firewalls. Flint can work with Playbook by ensuring any changes to firewalls are correct and don't open security holes into the network, according to Matasano. Flint also can run as a standalone tool for checking firewalls.

The tool also offers insight on complex firewall configurations and how they are working -- or not -- within a firewall.

The Ruby on Rails-based tool is available for download as a virtual appliance for VMWare, and Matasano also is offering the source code. The first version of Flint supports Cisco firewalls. "This is not a plug-in," Ptacek says. "We want this to have a life of its own."

Ptacek says Matasano is making the source code available as well for those who want to rebrand or extend it. "It's easy to extend, and we're hoping to get a lot of feedback from the network security community," he says.

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