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Shouldn't this be a trusted certificate considering it's a wildcard SSL certificate?

That is, shouldn't * cover

Wildcard SSL certificate

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See also this blog post by SE employee Nick Craver, which touches on some related issues involving the implementation of SSL certificates for the SE network. – user1535629 Mar 2 '14 at 9:32
MSIE does not trust it either – kinokijuf Apr 13 '14 at 10:15

1 Answer 1

up vote 44 down vote accepted

The wildcard replaces only one part of the hostname, e.g. * covers or but not From RFC2818, section 3.1:

...Names may contain the wildcard character * which is considered to match any single domain name component or component fragment. E.g., * matches but not f*.com matches but not

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@ack__: Related info at… – Mechanical snail Feb 28 '14 at 22:52
There is no complete wildcard SSL. The solution in this case would have been to have a certificate with subject alternative names for at least * (exists), (exists) and * (missing). Something like *.* is not allowed. – Steffen Ullrich Feb 28 '14 at 23:05
RFC6125 tries to unify the different handling of certificates among HTTP, LDAP, SMTP etc, but it does not allow *.* or similar. In section 6.4.3 it clearly states that wildcards should only be used within the left-most label (item 1) and that a * should only be compared against the left-most label of the reference identifier (item 2). It explicitely forbids * to match Section 7.2 only acknowledges that not all previous specifications explicitly forbid something like *.*, but neither this RFC nor RFC2818 (HTTPS) allow it. – Steffen Ullrich Mar 1 '14 at 5:13
@SteffenUllrich - "... it does not allow *.* or similar." - Is there any rationale for why this restriction was put in place ? And, does that rationale still apply today ? I don't see any downside in allowing this, other than the lost revenue for SSL Certificate issuers. – Kevin Fegan Mar 5 '14 at 8:28
I don't know the real motivation, but I guess it is to let an organization better reflect it structure and control. You often have a main organisation (like university) with a website and then sub-organisations (like department) which manage their own infrastructure. In this case it would be bad if a compromise of the *.university certificate would make it possible to overwrite all * certificates. – Steffen Ullrich Mar 5 '14 at 16:24

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