“This plug-in is vulnerable and should be updated” browser error

By: Matthew Adams
3 minute read
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Microsoft, Google and Mozilla have all been abandoning NPAPI plug-ins in their browsers. Thus, plug-ins are increasingly becoming history on the web. Adobe Flash is one notable exception as Google Chrome and Firefox still actively support that plug-in. Consequently, plug-in related error messages are also becoming rarer. However, “This plug-in is vulnerable and should be updated” is a plug-in error message that might still appear on some pages open in the Firefox browser.

“This plug-in is vulnerable and should be updated” [FIX]

Update the Flash Plug-in

The error message suggests that a plug-in needs updating. So it might be the case that you need to update Flash. This is how you can update Adobe Flash for Firefox.

  • First, open this website page to check if you need to install or update Flash. The page will tell if you Flash isn’t installed and if you need to update it.
  • To update Flash, open this website page; and deselect the optional offers check boxes if you don’t need the extra software.
  • Press the Install Now button to save the Flash installer.
  • Once you’ve saved the Flash installer to a folder, close Firefox.
  • Then open the Adobe Installer below, and press the Next button to update the plug-in.

Update Firefox

  • If you’re not using the most update Firefox version, you should also update the browser. Click the Open menu button at the top right of Firefox, and select Open Help Menu to expand a Help menu.
  • Next, select About Firefox to open the window below.

  • Firefox will now check for updates. If there are any, you can press a Restart Firefox to Update button.

Check the Flash Plug-in is enabled

  • Another thing to check is that Flash is on and active. To do that, press Open menu and click Add-ons to open the tab directly below.

  • Next, click Plug-ins on the left of the tab.
  • If Shockwave Flash is configured to Never Activate, click its drop-down menu and select Ask to Activate. Then the browser asks permission to activate Flash.

Allow Flash on Trusted Sites

If you’re still getting the “This plug-in is vulnerable and should be updated” error on pages, click the Activate Adobe Flash link just below it. Then a pop-up menu opens at the top left of the browser with two options to select from. Press the Allow and Remember button there to activate Flash on the website page every time you open it. Selecting Allow now will activate the plug-in only the one time, but blocks it again the next time you visit the site.

Disable the “This plug-in is vulnerable and should be updated” Error Message

  • Another way that you can ensure the plug-in error message never displays in Firefox is to disable it. You can do that by entering ‘about:config’ in the Firefox URL bar to open the page below.

  • Next, enter ‘extensions.blocklist.enabled’ in the search box.
  • Now double-click extensions.blocklist.enabled to switch it to false.

  • Restart the Firefox browser. The plug-in error message will no longer appear in Firefox.

Flash will also probably no longer be a supported Firefox plug-in a few years from now. Then all plug-in error messages should be a thing of history. Until then, keep Flash updated in your browsers to ensure there are no plug-in error messages.


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