[root@vagrant-centos65 you-get]# curl -v https://api.xxx.cn * About to connect() to api.xxx.cn port 443 (#0) * Trying 123.xxx.xx.xx... connected * Connected to api.xxx.
curl 7.19.7 (x86_64-redhat-linux-gnu) libcurl/7.19.7 NSS/3.19.1 Basic ECC zlib/1.2.3 libidn/1.18 libssh2/1.4.2
You are using a very old version of curl. My guess is that you run into the bug described 6 years ago. Fix is to update your curl.
If updating cURL doesn't fix it, updating NSS should do the trick.
If you are using curl versions curl-7.19.7-46.el6.x86_64 or older. Please provide an option as -k1 (small K1).