If you use target=”_blank” you need to also use rel=”noopener noreferrer”
Ben Halpern writes:
If you use the target=”_blank” attribute on a link, and do not accompany it with a rel=”noopener” attribute, you are leaving your users open to a very simple phishing attack.
When a website uses target=”_blank” on their links in order to open a new tab or window, that website gives the new page access to the existing window through the window.opener API, allowing it a few permissions. Some of these permissions are automatically negated by cross-domain restrictions, but window.location is fair game.
In order to restrict the behavior window.opener access, the original page needs to add a rel=”noopener” attribute to any link that has target=”_blank”. However, Firefox does not support that tag, so you should actually use rel=”noopener noreferrer” for full coverage. Some amount of prevention can be acheived through scripting, though, as observed with Twitter, this seems to fail on Safari.
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