Certificate Pinner

Certificate Pinner

Pins TLS certificates of configured web pages and interrupts/alerts when a new certificate is presented. Adds a button to the browser's toolbar for pinning and unpinning.

What is Certificate Pinner?
Certificate Pinner is a Firefox add-on that allows you to pin TLS certificates of web pages. It compares fingerprints, interrupts the authentication process for suspicious changes, and provides a warning with details to verify the certificate change. Safeguard your data with this handy tool.
Merlin
Stats
By: Heurekus
Users: 90 ▼ -1
Rating: 4.33 (9)
Version: 0.17.10 (Last updated: 2020-07-10)
Creation date: 2019-06-18
Weekly download count: 4
Firefox on Android: Yes
Risk impact: High risk impact
Risk likelihood: Low risk likelihood
Manifest version: 2
Permissions:
  • notifications
  • tabs
  • activeTab
  • storage
  • webRequest
  • webRequestBlocking
  • <all_urls>
Size: 33.13K
URLs: Website
Stats date:

Other platforms

Not available on Chrome
Not available on Edge
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Merlin
Summary

This add-on allows to selectively 'pin' TLS certificates of web pages. Whenever a page is loaded and the connection is TLS encrypted, it compares the fingerprint of the presented TLS certificate to the one that is stored. If they don't match, the TLS authentication process is interrupted before any local secrets such as session cookies, passwords, etc. are sent to the server. A tab is opened with a warning and details of the new certificate so the user can decide if the change is genuine. If so, the old fingerprint is replaced with the new fingerprint in local storage. A new button in the browser's toolbar opens a pop-up menu to pin and un-pin page certificates and to get a list of all pinned certificates.

User reviews
Not working with ip addresses (only with domains)
by Harliff, 2023-02-08
View all user reviews
Safety
Risk impact

Certificate Pinner is risky to use as it requires a number of sensitive permissions that can potentially harm your browser and steal your data. Exercise caution when installing this add-on. Review carefully before installing. We recommend that you only install Certificate Pinner if you trust the publisher.

Risk likelihood

Certificate Pinner has earned a fairly good reputation and likely can be trusted.

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Screenshots