Debian comes with an outdated OpenSSL version which has security vulnerabilities.
apt-get install autoconf python libtool build-essential
wget ftp://ftp.openssl.org/source/openssl-1.0.2i.tar.gz tar xfz openssl-1.0.2i.tar.gz
cd openssl-1.0.2i ./config --prefix=/usr zlib-dynamic --openssldir=/etc/ssl shared make make test sudo make sudo make install
openssl version