glb Meetup Tag Extension Link Attribute reverse tabnabbing

The glb Meetup Tag Extension for MediaWiki allows links to open new windows that can access the original page through window.opener, potentially letting attackers redirect users or manipulate the source page. This is known as reverse tabnabbing and can be used for phishing or malicious redirects.

The Link Attribute Handler in glb Meetup Tag Extension 0.1 fails to properly secure external links opened in new tabs/windows, allowing the opened page to access and manipulate the opener window via window.opener. An attacker can craft a malicious link that, when clicked, opens a controlled page with the ability to redirect or modify the original MediaWiki page, facilitating phishing or session hijacking attacks. Upgrade to version 0.2 to remediate.