VMware has published a patch for ESXi 5.1 and the corresponding vCenter Server version.
The SSLv3 issue has been addressed in this releases. Support for SSLv3 protocol is enabled by default but is configurable. This removes the risk of an unmanageable ESXi hosts when you update ESXi to the latest version, without having the latest vCenter Server.
To disable SSLv3 in your vSphere environment, you need to update ESXi to ESXi 5.1 build 3872664 released on May 24, 2016 and update vCenter Server to vCenter Server 5.1 Update 3d first and then manually disable SSLv3 through configuration settings, for more information, see KB2139396.