It appears that in order to include certain characters in the security.ldap.bind.queryPassword configuration variable, quoting is required, even for characters that are not considered special by the yaml standard.

One example of a password that requires quoting is p@ssword! . I believe neither @ nor ! require quoting in the yaml standard.

As far as I know, there is no documentation in MongoDB as to which characters require quoting. This can lead to an unoptimal experience for the user, for they would have to guess that the password requires quoting as part of their troubleshooting.