Trailrunner7 writes: Mozilla is planning to add support for public-key pinning in its Firefox browser in an upcoming version. In version 32, which would be the next stable version of the browser, Firefox will have key pins for a long list of sites, including many of Mozilla's own sites, all of the sites pinned in Google Chrome and several Twitter sites. Public-key pinning has emerged as an important defense against a variety of attacks, especially man-in-the-middle attacks and the issuance of fraudulent certificates. The function essentially ties a public key, or set of keys, issued by known-good certificate authorities to a given domain. So if a user's browser encounters a site that's presenting a certificate that isn't included in the set of pinned public keys for that domain, it will then reject the connection. The idea is to prevent attackers from using fake certificates in order to intercept secure traffic between a user and the target site.