Debian Linux Security Advisory 1935-1 - Dan Kaminsky and Moxie Marlinspike discovered that gnutls, an implementation of the TLS/SSL protocol, does not properly handle a '\\0' character in a domain name in the subject's Common Name or Subject Alternative Name (SAN) field of an X.509 certificate, which allows man-in-the-middle attackers to spoof arbitrary SSL servers via a crafted certificate issued by a legitimate Certification Authority. In addition, with this update, certificates with MD2 hash signatures are no longer accepted since they're no longer considered cryptograhically secure.
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