This error occurs due to Git’s HTTPS protocol. To view the error in detail, you can set the GIT_CURL_VERBOSE
environment variable. For example:
$ GIT_CURL_VERBOSE=1 git pull
Your Antivirus or Firewall could be modifying the HTTP packets in transit. See git clone failed due to antivirus for example.
Finally, it could be an unreliable network connection. I am using an OSX machine connected to Wifi, and the problem disappeared when I switch to a LAN connection.