Facebook, Twitter, Google, Microsoft and many other online services users have been hit by a serious new security flaw.
The flaw in two widely used security standards could give anyone access to your account information at any of the online services.
According to Fox News, the flaw, dubbed 'Covert Redirect' by its discoverer, exists in two open-source session-authorization protocols, OAuth 2.0 and OpenID.
Both standards are employed across the Internet to let users log into websites using their credentials from other sites.
Attackers could exploit the flaw to disguise and launch phishing attempts from legitimate websites.
According to the report, the biggest danger of Covert Redirect is that it could be used to conduct phishing attacks, in which cyber criminals seize login credentials, by using email messages containing links to malicious websites disguised as something their targets might want to visit.