The ssl_Do1stHandshake function in sslsecur.c in libssl in Mozilla Network Security Services (NSS) before 3.15.4, when the TLS False Start feature is enabled, allows man-in-the-middle attackers to spoof SSL servers by using an arbitrary X.509 certificate during certain handshake traffic. http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2013-1740
