Signed Pages is a browser extension to verify the authenticity (PGP signature) of web pages.

Why?

This extension was originally created to improve the security of the EteSync web app (https://www.etesync.com). One of the biggest issues with securing web applications is the fact that the app (JavaScript) is delivered to you every time you open the page. This means that a malicious (or compromised) web server could change the code to steal your supposedly client-side-only and secure data.

This extension solves this by verifying the code really came from the developer. While this doesn't protect you from a malicious developer, it at least brings the security of the web app to a similar level to that of native apps.

Usage

All you need to do is install the extension, and from its settings page, add patterns to match pages you'd like to verify, and their corresponding publisher's public key. The developers of those websites must have their pages signed for this extension to work.

Example pages

You can try the following example pages to see how the extension behaves:

Install the extension and add the pattern and pubkey shown in the page from the extension's settings.

• A page with a good signature: https://stosb.com/~tom/signed-pages/good.html
• A page with a bad signature: https://stosb.com/~tom/signed-pages/bad.html
• A page with a missing (but expected) signature: https://stosb.com/~tom/signed-pages/missing.html

More info and source code:

https://github.com/tasn/webext-signed-pages

Attribution

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• Shield made by [Smashicons](https://www.flaticon.com/authors/smashicons) and licensed as [CC 3.0 BY](http://creativecommons.org/licenses/by/3.0/)
• Checked made by [Eleonor Wang](https://www.flaticon.com/authors/eleonor-wang) and licensed as [CC 3.0 BY](http://creativecommons.org/licenses/by/3.0/)
• Fingerprint made by [Google](https://www.flaticon.com/authors/google) and licensed as [CC 3.0 BY](http://creativecommons.org/licenses/by/3.0/)