The timing attack protection in Rijndael::Enc::ProcessAndXorBlock and Rijndael::Dec::ProcessAndXorBlock in Crypto++ (aka cryptopp) before 5.6.4 may be optimized out by the compiler, which allows attackers to conduct timing attacks.Referenceshttp://www.openwall.com/lists/oss-security/2016/04/11/2https://github.com/weidai11/cryptopp/issues/146http://www.securityfocus.com/bid/85975
