I&#x27;m pretty sure iOS updates are signed per device, as that&#x27;s why everyone backs up their signatures for old versions (so that they can go back while Apple isn&#x27;t signing them). So Apple could only sign this backdoor for one device.<p><a href="http:&#x2F;&#x2F;www.saurik.com&#x2F;id&#x2F;12" rel="nofollow">http:&#x2F;&#x2F;www.saurik.com&#x2F;id&#x2F;12</a>