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##### SUMMARY

The Git module encourages use of `StrictHostKeyChecking=no` with SSH, which makes the connection vulnerable to a MITM attack.

##### ISSUE TYPE

OpenSSH 7.5+ (2017-03-20) added a safer option which automatically accepts the key on first use but will not allow a MITM on subsequent connections: `StrictHostKeyChecking=accept-new` 

https://man.openbsd.org/ssh_config#StrictHostKeyChecking

It would be great if Ansible encouraged use of that mode by default in the documentation and to implement features such as the Git module's [`accept_hostkey`](https://github.com/ansible/ansible/blob/323d2adfcce9a53e906c2c4a40f6ac5fb32a0e68/lib/ansible/modules/git.py#L1103-L1108) feature.

##### ANSIBLE VERSION

```paste below
N/A
```

##### COMPONENT NAME
* `/modules/source_control/git.py`


'''Return URL of remote source for repo.'''
    command = [git_path, 'ls-remote', '--get-url', remote]
    (rc, out, err) = module.run_command(command, cwd=dest)
    if rc != 0:
        
        
        return None
    return to_native(out).rstrip('\n')
def set_remote_url(git_path, module, repo, dest, remote):
    ''' updates repo from remote sources '''
    
    remote_url = get_remote_url(git_path, module, dest, remote)
    if remote_url == repo or unfrackgitpath(remote_url) == unfrackgitpath(repo):
        return False
    command = [git_path, 'remote', 'set-url', remote, repo]
    (rc, out, err) = module.run_command(command, cwd=dest)
    if rc != 0:
        label = "set a new url %s for %s" % (repo, remote)
        module.fail_json(msg="Failed to %s: %s %s" % (label, out, err))
    
    
    return remote_url is not None
def fetch(git_path, module, repo, dest, version, remote, depth, bare, refspec, git_version_used, force=False):