Help/variable/CMAKE_TLS_VERIFY.rst
Specify the default value for the :command:file(DOWNLOAD) and
:command:file(UPLOAD) commands' TLS_VERIFY options.
If this variable is not set, the commands check the
:envvar:CMAKE_TLS_VERIFY environment variable.
If neither is set, the default is on.
.. versionchanged:: 3.31
The default is on. Previously, the default was off.
Users may set the :envvar:CMAKE_TLS_VERIFY environment
variable to 0 to restore the old default.
This variable is also used by the :module:ExternalProject and
:module:FetchContent modules for internal calls to :command:file(DOWNLOAD).
TLS verification can help provide confidence that one is connecting to the desired server. When downloading known content, one should also use file hashes to verify it.
.. code-block:: cmake
set(CMAKE_TLS_VERIFY TRUE)