diff --git a/src/cmlxc/incus.py b/src/cmlxc/incus.py
index 18fb3c9..a63c284 100644
--- a/src/cmlxc/incus.py
+++ b/src/cmlxc/incus.py
@@ -88,6 +88,7 @@ def write_ssh_config(self):
         containers = self.list_managed()
         text = format_ssh_config(containers, self.ssh_key_path)
         self.ssh_config_path.write_text(text)
+        self.ssh_config_path.chmod(0o600)
         return self.ssh_config_path
 
     def check_ssh_include(self):