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30-seconds-of-code/snippets/javascript-target-blank.md
2023-04-28 22:35:56 +03:00

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---
title: 'Tip: Protect your users from malicious websites when using target="_blank"'
shortTitle: 'Safeguarding target="_blank"'
type: tip
tags: [javascript,browser,security]
author: chalarangelo
cover: laptop-with-code
excerpt: Opening a link in a new tab comes with a security vulnerability that you may not be aware of. Protect your users with this simple trick.
dateModified: 2021-06-12T19:30:41+03:00
---
Oftentimes, when linking to an external resource from our websites, we use `target="_blank"` to open the linked page in a new tab or window. But there is a security risk we should be aware of. The new tab gains limited access to the linking page (i.e. our website) via `Window.opener`, which it can then use to alter the linking page's URL via `Window.opener.location` (this is known as tabnabbing).
This might be a problem if the external resource is not trustworthy, might have been hacked, the domain has changed owners over the years etc. There is no guarantee that a third-party resource, no matter how trustworthy, can be actually trusted with our users' security and we, as developers, should always be aware of this risk.
```html
<!-- Bad: susceptible to tabnabbing -->
<a href="https://externalresource.com/some-page" target="_blank">
External resource
</a>
<!-- Good: new tab cannot cause problems -->
<a
href="https://externalresource.com/some-page"
target="_blank"
rel="noopener noreferrer"
>
External resource
</a>
```
In order to prevent a link that is opened in a new tab from causing any trouble, we should always add the `rel="noopener noreferrer"` attribute to all of our `target="_blank"` links.