You can use obfuscation password. Use Xauth obfuscated password XXXXXX.
Remember that an obfuscation password can be defoxed using a utility cisco-decrypt.
You can create an obfuscation password using a tool cisco-encryptthat you can build using the code provided here .
Do it like
gcc -o cisco-encrypt cisco-encrypt.c -lgcrypt
(libgcrypt required)