Protecting your computer from unwanted guests: Firefox with NoScript

In the final post of this series I'll look at my favorite tool, Firefox with the NoScript plugin. Firefox is a browser by Mozilla and NoScript is a plugin that can be installed on Firefox. What NoScript essentially does is blacklist all the "JavaScript, Java, Flash, and other plugins" running on websites. It also provides cross-site scripting (XSS) and clickjacking protection.

After downloading and installing Firefox, go to the NoScript site or plugin page and install it to Firefox. A reboot of the browser will be required, but NoScript will be up and running. Now comes the annoying part. Every website and every script running on that website will require your approval to run. This is great for avoiding malware and web ads, but means that a page might not run properly when you first visit it.

To allow a web page and some scripts that will be needed to perform functions on the web page, click on the NoScript icon, which is an 'S' with a prohibition sign. Click on the main web page and allow, this will provide some more functionality on the page as well as open up more scripts to unblock. And that's the tricky part figuring out which scripts to allow to run. A Google search can help with this, but sometimes it's just trial and error to allow the right script to get the function you want to run. If you get frustrated enough you can 'temporarily allow all this page,' 'allow all this page,' or 'Allow Scripts Globally (dangerous).' Allowing scripts globally will essentially disable the plugin and I would avoid if you can. Temporarily will allow as long as the browser is open and allow all this page will allow all the scripts on the page permanently. Some scripts might run on multiple sites, so allowing them once allows them for all websites.

This method of protection will require the most work on your part, but also provides the most security when browsing the web. Accidentally clicked the wrong link? No worries, the script that installed the nasty malware never had a chance to run. You'll also get to see all the useless crap companies put on their web pages.

This the final post in my series on Protecting your computer from unwanted guests. This was mainly to provide my brother a walkthrough for protecting his computers at work, but if any other security professionals would like to chime in with tips or other suggestion, I would love that.

Protecting your computer from unwanted guests: EMET

One of the awesome under-publicized tools that does an awesome job of hardening a computer is Microsoft's Enhanced Mitigation Experience Toolkit or EMET for short. This tool helps vulnerabilities in software from being exploited. It's not foolproof and researches have found ways around it, but it is effective. I've seen it be effective first hand. The tool is easy to install and manage, but will require some action on your part.

Download EMET and run the install. As part of the installation select 'Use Recommended Settings' then click 'Finish' and 'Close.' Once installed, right click on the EMET icon in the bottom right corner of the screen or the box thingy that pops up by click on the triangle on the task bar. Ensure that Data Execution Prevention (DEP) is set to 'Always On,' Structured Exception Handler Overwrite Protection (SEHOP) is set to 'Application Opt In,' Address Space Layout Randomization (ASLR) is set to 'Application Opt In,' and Certificate Trust (Pinning) is set to 'Enabled.' And that is pretty much it. EMET is now running on your computer kicking ass.

Unfortunately, EMET also steps in and kicks the ass of a legitimate like its cousins Internet Explorer and Microsoft Office applications or some other program. To fix this look at the alert and look at what the program is being blocked for. Then click on the 'Apps' button in the configuration section and uncheck the box of the blocking action for that application.

For more information on the tool you can download the user guide with the EMET installation. Also, Windows Update will not keep EMET up-to-date and will require a manual download and installation of any new version releases.

Protecting your computer from unwanted guests: software patching

Patching is an important part of protecting a computer from unwanted guests. It is that process where we like to hit 'Install later' when a new patch becomes available.

Windows updates should be straight forward and already set to automatically run when new patches come in. To check that this is in fact the case do the following:

Click Start -> Control Panel -> Windows Update. On the left hand side click 'Change settings.' In the 'Important updates' section click the drop down and select 'Install updates automatically (recommended).' Set a date and time. Mine are set to 'Every day' and at '3 a.m.'

For all non-Microsoft software use Secunia Personal Software Inspector (PSI). This is a free tool for home (commercial is paid) use that goes out and grabs and installs all the updates for most of the third party software installed on a machine. Some updates will require manual installation, but most won't require any action from you at all. Simply download, install, and forget. Well, except for the manual installs that should be checked for every once and a while. 

Protecting your computer from unwanted guests

My brother and I in Holland, in a big ass clog, keeping out feet protected from bad...things.

My brother and I in Holland, in a big ass clog, keeping out feet protected from bad...things.

My brother recently contacted me about an incident involving a tech support scam. Luckily, the scam was caught before anything serious happened and one good thing came out of the episode, which leads me to this post and the next few posts. I will be going over some of the tools that can be used to keep unwanted guests out of a computer. All the tools I will be talking about are free, but will require some configuration and thinking.


Here are the four tools I recommend for avoiding those nasty Internet Transmittal  Diseases (ITD):

  • Microsoft Security Essentials - Anti-virus
  • Secunia Personal Software Inspector (PSI) - Software patching
  • Microsoft Enhance Mitigation Experience Toolkit (EMET) - Computer hardening
  • Mozilla Firefox with NoScript plugin - Safe browsing
  • BONUS: Turn on click-to-play in browsers

I want go in-depth on Microsoft Security Essentials and turning on click-to-play in browsers. For Security Essentials, go to the download page, download, and install. Simple as that. There aren't many settings for the anti-virus program and that's a good thing. Anti-virus is largely mocked within the infosec community, because it's easy to circumvent, and that includes the $40-60 big name anti-virus companies of the world. Still, it has saved my bacon a time or two and worth installing, especially if it's free like Security Essentials.

I covered click-to-play in my last post and provided a link to a pretty good article that goes through how to turn on click-to-play in all the browsers. No need to reinvent the wheel, so here's the link again. Click-to-play is easy to turn on and easy to get used to and helps with computer performance.

If any of the posts are unclear are you have a questions, please leave a comment or contact me directly.