The Disadvantages of a Firewall

By Kefa Olang

Protect data with anti-hacking precautions.
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As the first line of defense on a computer, firewalls are primarily designed to limit or stop network traffic and connections. Firewalls analyze incoming data, what it intends to do, and where it's going to determine whether it should be accepted or denied based on the firewall's policy. Although firewalls can protect your computer because they require authentication to open network-intensive programs, they may interfere with known safe operations and are limited in their protection capabilities.


Firewalls are central points of attack. Firewalls are designed to prevent unauthorized network intrusions; however, if an intruder or malware slips through the system, your computer becomes vulnerable to additional system attacks, even total control from a malicious party. When malware such as Trojans attempt to install, they first must get past the firewall. This can happen by way of email, for example. Once installed, malware can actually disable the firewall and processes used to run it, which is especially easy if you have no anti-virus software.

Blocking Legitimate Processes

A firewall, especially the Windows Firewall, is designed to block activities that look suspicious. Unfortunately, a block can also extend to legitimate network-intensive processes. In some cases, even running a legitimate program such as a messaging program or social networking plug-in won't work if your firewall concludes it's a malicious process. How weak or strong blocks are depends on your firewall's settings and configurations, so it's always important to adjust your program's settings accordingly. If a legitimate program is unable to connect to your network, verify it's added to your firewall's exceptions list, a database that contains a list of programs allowed to connect to your network.

Malware Removal

Firewalls, especially the Windows Firewall, don't include malware and virus removal capabilities. Although there are some premium security tools that include virus removal and a firewall to block network intrusions, the Windows Firewall doesn't remove or prevent malware. If malware such as Trojans and spyware bypass your firewall, you must run virus scans and malware removal programs to remove dangerous files. Firewalls are also incapable of protecting your computer against backdoor Trojans, programs that open ports on your computer and send information to a hacker, who then controls your system from a remote location.

Data Protection

Firewalls provide a line of defense against malicious tactics that can cause system problems, but they're incapable of protecting your computer alone. If you're using the Windows Firewall, make sure it's turned on from the Control Panel. The Windows Firewall, for example, tells you whether your computer has an anti-virus program or not. If an anti-virus program is non-existent, it recommends installing one to improve system security. Firewalls are also not designed to ensure data confidentiality. Websites that promote phishing, activities designed to steal personal information such as passwords and credit card numbers, can use emails and links to steal information. Unless your firewall includes encryption tools, you're still at risk of losing personal information to the wrong people.