mod-gnutls does not validate client certificates when "GnuTLSClientVerify require" is set in a directory context, which allows remote attackers to spoof clients via a crafted certificate.Referenceshttp://issues.outoforder.cc/view.php?id=93https://bugzilla.redhat.com/show_bug.cgi?id=1197127https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=578663http://www.openwall.com/lists/oss-security/2015/02/26/6
