By Joe Pinkstone For Mailonline
Published: 17:10 GMT, 10 January 2020 | Updated: 17:12 GMT, 10 January 2020
Mozilla has been forced to rush out a fix to its Firefox browser after it was revealed a critical vulnerability was allowing hackers to target users.
The US Cybersecurity and Infrastructure Security Agency (CISA) revealed the vulnerability could allowed criminals to seize total control of the browser.
Mozilla said it had found evidence that hackers were actively exploiting the vulnerability in 'targeted attacks' against users.
Mozilla prides itself on stringent security protocols and ushered out an automatic update with a patch for the vulnerability.
Users are urged to update the browser manually to ensure they are fully protected from any attacks.
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Mozilla has made a concerted effort to court users away from other browsers like Google Chrome by building privacy into its experience but a serious flaw this week exposed customers
The fix was sent out on Wednesday in an automatic update.
Users should manually update their app to ensure they are fully protected.
To do so, open your browser, click on 'Firefox' in the top menu, and then select 'About Firefox.'
A popup window will open and assess which version of the browser you're running.
f you have an older version of the browser, it'll automatically update and then ask you to restart your browser.
All your open windows will be restored.
The browser will then be fully up to date.
The CISA said in a statement: 'Mozilla has released security updates to address a vulnerability in Firefox and Firefox ESR.
'An attacker could exploit this vulnerability to take control of an affected system.