升级OpenSSL
首先下载解压最新的 OpenSSL

wget https://github.com/openssl/openssl/archive/OpenSSL_1_1_1-stable.zip
unzip OpenSSL_1_1_1-stable.zip
然后就是编译安装了

./config --prefix=/usr/local/openssl // 指定安装路径
make && make install
最后替换当前系统的旧版本 openssl 「先保存原来的」

mv /usr/bin/openssl /usr/bin/openssl.old
mv /usr/lib64/openssl /usr/lib64/openssl.old
mv /usr/lib64/libssl.so /usr/lib64/libssl.so.old
ln -s /usr/local/openssl/bin/openssl /usr/bin/openssl
ln -s /usr/local/openssl/include/openssl /usr/include/openssl
ln -s /usr/local/openssl/lib/libssl.so /usr/lib64/libssl.so
echo "/usr/local/openssl/lib" >> /etc/ld.so.conf
ldconfig -v 
最后查看当前系统 openssl 版本

openssl version

mv /etc/ssh /etc/ssh.old
mv /etc/init.d/sshd /etc/init.d/sshd.old
mv /bin/ssh /bin/ssh.old
mv /bin/ssh-add /bin/ssh-add.old
mv /bin/ssh-agent /bin/ssh-agent.old
mv /bin/ssh-copy-id /bin/ssh-copy-id.old
mv /bin/ssh-keygen /bin/ssh-keygen.old
mv /bin/ssh-keyscan /bin/ssh-keyscan.old

mv /usr/bin/ssh /bin/ssh.old
mv /usr/bin/ssh-add /bin/ssh-add.old
mv /usr/bin/ssh-agent /bin/ssh-agent.old
mv /usr/bin/ssh-copy-id /bin/ssh-copy-id.old
mv /usr/bin/ssh-keygen /bin/ssh-keygen.old
mv /usr/bin/ssh-keyscan /bin/ssh-keyscan.old

mv /usr/sbin/sshd /usr/sbin/sshd.old
mv /usr/sbin/ssh-keygen /usr/sbin/ssh-keygen.old

yum install zlib-devel pam-devel

./configure \
  --prefix=/usr \
  --sysconfdir=/etc/ssh \
  --with-md5-passwords \
  --with-pam \
  --with-tcp-wrappers \
  --with-ssl-dir=/usr/local/openssl \
  --without-hardening
  
make && make install

cp -rp /usr/local/src/openssh-8.4p1/contrib/redhat/sshd.init /etc/init.d/sshd
chkconfig --add sshd
systemctl enable sshd
systemctl restart sshd