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Mozilla Foundation Security Advisory 2013-113

Trust settings for built-in roots ignored during EV certificate validation

Announced
December 10, 2013
Reporter
Sijie Xia
Impact
Moderate
Products
Firefox, Firefox ESR, SeaMonkey, Thunderbird
Fixed in
  • Firefox 26
  • Firefox ESR 24.2
  • SeaMonkey 2.23
  • Thunderbird 24.2

Description

Firefox user Sijie Xia reported that if a user explicitly removes the trust for extended validation (EV) capable root certificates in the certificate manager, the change is not properly used when validating EV certificates, causing the setting to be ignored. This removes the ability of users to explicitly untrust root certificates from specific certificate authorities.

This flaw does not affect certificates that are not extended validation certificates. All other certificate validation checks do occur, the error is the assumption that if Mozilla trusted the certificate, the user would also.

References