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ZendXmlRpc Class in Magento before 1.7.0.2 contains an information disclosure vulnerability.
Magento 1.5 and 1.6.2 does not verify that the server hostname matches a domain name in the subject's Common Name (CN) or subjectAltName field of the X.509 certificate, which allows man-in-the-middle attackers to spoof SSL servers via an arbitrary valid certificate.