The trick to test your security password is to try to reset the password with a new password which is based on a dictionary word!

set password user security

Dictionary Word password that will fail: “cisco123”
you will get the warning and Select 'y' to continue.
If the Old password is entered correctly - you will get the following error when you attempt to change the password:

"BAD PASSWORD: It is based on a dictionary word"

If the old password is incorrect, you will a different error (as below) and hence you can validate if your security password is as you suspect or not!

"The old password did not match"

Reference: https://supportforums.cisco.com/document/65041/how-reset-passwords-cucm#Security_password
https://supportforums.cisco.com/discussion/11434381/how-can-i-validate-security-password-cucm-86