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Security & privacy

Update Firefox now! Critical security flaws leave you vulnerable to hacks

We all know that the end is near for Flash. By 2020, Adobe will finally kill Flash off by ending support for it completely. While it is still a ways off, this will give web developers time who still use Flash to transition to newer technologies like HTML5 and web browser makers to gradually drop it off completely.

These past few years, we’ve seen all the popular browsers like Google Chrome, Microsoft Edge, and Mozilla Firefox demote Flash to a disabled-by-default plugin and by blocking Flash content automatically. While Firefox started blocking “certain Flash content that is not essential to the user experience” last year, its latest update will put Flash closer to its grave.

Firefox 55

Mozilla released a major update for Firefox last week that brought with it new features, bug fixes and another step in its Flash phase-out plan. Starting with Firefox 55, Flash in Firefox will be “click-to-play” by default and will only run on “http” or “https” URLs.

This means that by default, users will have to explicitly allow a webpage or parts of a webpage to run Flash content. Although this default behavior can still be changed in Firefox’s settings, this latest update follows through Mozilla’s phase-out plan for the antiquated web plugin. Additionally, in line with the plan, once support for Flash is dropped completely by Adobe, Firefox will no longer load the Flash plugin.

Although included in Firefox 55, this”click-to-play” change for the Firefox’s Flash plugin is being rolled out progressively in the next few months so keep checking for the latest updates.

Security fixes

Aside from the Flash plugin change included in Firefox 55 are security fixes for three critical flaws and 11 high-impact vulnerabilities.

One of the critical flaws would have allowed an attacker to execute remote code and take over a computer.

The other critical bugs are use-after-free vulnerabilities that can lead to browser crashes. Other issues fixed are high-severity buffer overflows, a same-origin bypass and more use-after-free flaws. These flaws could lead to browser crashes, information disclosure and they could bypass Firefox’s memory protections.

More features

Other new tweaks and features include support for Virtual Reality and major performance boosts, which aim to speed up Firefox’s browsing experience even further.

Ready to update to Firefox 55? Here’s how you do it.

Firefox ordinarily updates itself when you open it; this is the default setting. But if it hasn’t, visit for the latest version.

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