The Internet Threat
By Ed Duncan, Consultant, SBSC, MCSE, MCSA
Security has become a major part of the IT industry. Fifteen years ago security was an afterthought when developing applications, building computer infrastructures, or even accessing the Internet. Today businesses can't begin to implement a strong infrastructure without planning a security foundation first. The topic of security is so broad, that we can probably talk about it for the next three months as the featured topic for this newsletter and still not cover every aspect of it.
We will not do that, but we will this month focus on the threats from the Internet and what small business owners can do to protect themselves. With many companies, large and small, relying on the Internet to conduct main portions of their business, a good security policy and implementation is vital to the success of small businesses.
Many companies and consumers alike rely on a firewall as their first line of defense against threats from the Internet. Firewalls can either be software based or a hardware device, that functions to block certain forms of Internet traffic from reaching your computer if it doesn't meet certain rules. Many Internet Service Providers offer firewall protection as a service, nearly every anti-virus vendor includes a firewall with their products, and even Windows has a crude built-in firewall in its operating systems. While highly effective as an access blocking defense measure, firewalls are only one form of protection, and can prove to be ineffective at other threats and forms of malware designed to work around them.
Consider web pages for example. Most use port 80 over the http protocol, which you don't want to block on your firewall or you won't be able to access the Internet at all. Web pages are becoming the number one source of Internet attacks with hackers injecting malicious code into many legitimate websites. When a browser that is not patched or susceptible to the specific type of malicious code that resides on the web page, the computer can become infected and carry out commands like return sensitive data such as credit card numbers, email addresses, contact information, or it can act as a computer zombie spreading the code to other computers on the network. Social networking sites are popular targets for these types of attacks.
Web filters are a good defense against these types of attacks. Web filters sort of work like firewalls in reverse. They block computers in your internal network from accessing websites based on content. So for example, if you don't want anyone in your company accessing social networking sites, you can configure the web filter to block access to all social networking sites, without you having to know the names of all the sites out there. Web filters generally work off a database that is updated constantly, so as new sites are created, they are automatically rated and categorized based on content. As a security measure web filters can also protect your business from phishing sites, and other popular sites that hackers tend to target like P2P file sharing sites, gaming sites, and online shopping sites.
Like firewalls, web filters are good but can be ineffective at stopping other forms of malware attacks. Emails and Instant Messaging continue to be an old but effective method of attacks. You can be tricked into opening emails or IMs that appear as legitimate from your friends, but in fact are Trojan horses disguised to get you to run infected code, or click a link to a malicious website. To combat these types of attacks a good anti-virus client is needed. Be sure to pick an anti-virus client that is capable of scanning incoming and outgoing email messages, provides spam blocking, as well as scanning Instant Messages. An AV client with real-time scanning capabilities is a must, and automatic updating is also important.
Another method you can use to protect yourself on the web is to use browsers that offer a privacy mode. This will allow you to visit sites without those sites collecting information about you, or dropping cookies on your computer. Also keep your browser up to date with the latest security patches. There are security watchdog groups that try to uncover and expose vulnerabilities in all the major browsers, and report them to the manufacturers when discovered. For their part, the manufacturers do an adequate job at addressing those vulnerabilities as quickly as possible by releasing hotfixes and security updates. Ultimately though, the burden falls on the network administrator or end user to get those patches installed on their computers.
While there is no method or procedure that will protect you against every threat and vulnerability that exist, using a multi-stage defense measure can help minimize the chance of becoming a target, and make your Internet experience a little more worrisome free.