For many years Spamhaus has been top dog in the anti-spam world of DNSBL (Domain Name System Block List; also known as Realtime Blackhole Lists or RBLs). But Spamhaus is no longer a 100% free service. Even small nonprofits are now expected to pay at least $250 per year for a subscription to the Spamhaus DNSBL Datafeed Service. Now a new, free alternative to Spamhaus has arrived: the Barracuda Reputation Block List (BRBL), provided by well-known, open source-based Barracuda Networks. And Barracuda CEO Dean Drako says the company has no plans to charge for the service in the future. He says that BRBL (pronounced "barbell") "does cost us a little bit of money to run, but we think that the goodwill, the reputation and the understanding that Barracuda is providing the service will do us well in the long run."
Corporations and home users alike need firewall protection. Many choices abound, including some expensive, commercial options that only run on specialized hardware. Others, like SmoothWall Express, are freely downloadable, built on the same technology as the commercial solutions, and even deliver some superior features.
When Maine State Employees Association SEIU Local 1989 needed software to safeguard confidential information and ward off online threats, it found an open source solution. The labor union, which represents more than 15,000 public and private sector workers throughout the State of Maine, chose Untangle's open source Gateway platform, a solution that not only helps keep confidential data away from prying eyes, but also protects against spam, spyware, phishing, and viruses.
You probably rely on the services on your own private network -- wikis, mail servers, Web sites, and other applications you've installed. What happens when you have to leave the friendly confines of your network? With minimum exposure and few simple tools, you can get all of the comforts of home anywhere you can find an Internet connection.
The pam_mount project lets you unlock an encrypted filesystem automatically when you log in. The same password used to log in is used as the key to unlock the encrypted filesystem, so you only need to type it once. Using this method, you can easily share a laptop and have only a single user's home directory unlocked and mounted when he logs in. And pam_mount can mount any filesystem, not just encrypted filesystems, so you can use it, for example, with an NFS share that you are interested in but which you might not like to leave mounted when you are not logged in.
The Metasploit Project develops a set of security tools to create and execute exploit code on remote computers. Some people say Metasploit makes the job easier for black hat hackers who attack networks looking for vulnerabilities to take advantage of; others says the tool helps network security administrators do a better job of finding and repairing weaknesses before the bad guys get to them. H.D. Moore, the 20-something creator of the Metasploit Project, says it all depends on your perspective.
It is good practice to use a different password for each Web site you need to log in to. Good passwords tend to be long and contain a wide selection of characters. That can make remembering all your passwords difficult. But you can make things easier on yourself by storing passwords for various Web sites in an encrypted file on your computer. I'll take a look at a four programs that give you easy access to your passwords when you need them and protect the password file itself against compromise.
When they hear the word PAM, most people think of a certain blonde Canadian Playmate, but readers of this Web site surely will recognize the basic element of Linux security: the Pluggable Authentication Modules. So let's talk about how this PAM works, and look at some examples of how it is used.
As important as security is, remaining current with every development is hard, and evaluating possible vulnerabilities across a network can be quite a chore. You need a way to both automate tests and make sure you're running the most appropriate and up-to-date tests. Open Vulnerability Assessment System (OpenVAS) is a network security scanner that includes a central server and a graphical front end. The server allows you to run several different network vulnerability tests (NVT) written in Nessus Attack Scripting Language (NASL), which OpenVAS updates frequently.
pfSense is a free, powerful firewall and routing application that allows you to expand your network without compromising its security. Started in 2004 as a child project of m0n0wall -- a security project that focuses on embedded systems -- pfSense has had more than 1 million downloads and is used to protect networks of all sizes, from home offices to large enterprises. pfSense has an active development community, and more features are being added in each release to further improve its flexibility, scalability, and, of course, security.
The Uncomplicated Firewall (UFW) is a new tool from Ubuntu whose goal is to make configuration of the built-in Linux packet filter less complicated and more secure for novice users.
gnoMint is a desktop application that lets you easily manage your own certificate authority (CA). Many secure communications technologies use digital certificates to ensure that the party or service they are connecting with is not an impostor. For many people, the main exposure to digital certificates comes when they visit an HTTPS Web site and see a certificate to validate that they have contacted the right Web server.
Almost every laptop on sale today comes equipped with the Kensington security slot on the side or back, through which you can connect a theft-deterring locked steel cable. The system's down sides are (a) that a would-be thief can damage or destroy your equipment trying to yank the cable out, and (b) that you have to buy the cable separately. As an alternative, the free software utility Adeona won't preemptively deter theft, but it will help you track down your stolen equipment and better the chances of its recovery by police.
Network access control (NAC) aims to unify endpoint security, system authentication, and security enforcement in a more intelligent network access solution than simple firewalls. NAC ensures that every workstation accessing the network conforms to a security policy and can take remedial actions on workstations if necessary. For example, NACs can check if a workstation has antivirus software installed and, if not, NAC will limit the workstation's access to the network. In some cases, if NAC is capable of remedial measures, it can force-install an antivirus program on the workstation so that it will conform to the security policy. Although NAC can improve the security of your environment, most commercial NACs cost several thousand dollars. However, using NAC does not need to be that expensive. PacketFence, a free open source NAC application, gives you the security of NAC for free.
Unified Threat Management (UTM) devices unify all network security elements into a single device. They often include a combination of routing, firewall, intrusion detection, content filtering, URL filtering, spam filtering, VPN, and antivirus functionalities. These devices usually cost thousands of dollars and require subscriptions. However, you can secure your network and save money at the same time with Endian Firewall Community, a free, open source alternative to costly UTM devices.
Being connected to the Internet means exposure to what the outside world has to offer -- including the undesirable elements. Every time you connect to the Internet, you're exposed to threats that can compromise your network's security. Although network security solutions have evolved in recent years, so have network attack techniques. To prevent ever-evolving attacks from compromising your network, you must preemptively block malicious traffic before it enters your network. Free, open source programs, such as Snort, can do the job, but setting up a full intrusion detection system (IDS) sensor, especially in an enterprise network, takes time and isn't very user-friendly. StillSecure's Strata Guard Free can be your front line of defense to face outside threats without as much hard work.
SQL injection attacks can allow hackers to execute arbitrary SQL commands on your database through your Web site. To avoid these attacks, every piece of data supplied by a user on a Web form, through HTTP Post or CGI parameters, or other means, must be validated to not contain information that is not expected. GreenSQL is a firewall for SQL -- it sits between your Web site and MySQL database and decides which SQL statements should and should not be executed. At least that's the idea -- in execution, I found some open doors.
Firewall Builder (fwbuilder) is a graphical application that can help you to configure IP traffic filtering. It can compile the filtering policy you define into many specifications, including iptables and various languages used by Cisco and Linksys routers. Separating the actual policy you define and the implementation in this way should let you change what hardware is running your firewall without having to redefine your policy for that platform.
Vyatta offers hardware and open source software for enterprise-level network infrastructure. Vyatta can turn any 32-bit x86 machine with at least one network interface into a network appliance that handles routing, firewall, and VPN tasks. The company released Vyatta Community Edition 4 in April, with improved scalability and feature enhancements. Large enterprises now have a low-cost alternative to proprietary hardware like the Cisco 7200.
To help developers audit Web application security, Google has released an open source tool called ratproxy. It is a non-disruptive tool designed for Web 2.0 and AJAX applications that produces an easy-to-read report of potential exploits.