Umbraco, a free and open source .NET content management system, has a vulnerability in versions 10.0.0 through 10.8.10 and 13.0.0 through 13.9.1. Via a request to an anonymously authenticated endpoint it's possible to retrieve information about the configured password requirements. The information available is limited but would perhaps give some additional detail useful for someone attempting to brute force derive a user's password. This information was not exposed in Umbraco 7 or 8, nor in 14 or higher versions. The vulnerability is patched in versions 10.8.11 and 13.9.2.

Umbraco CMS disclosure of configured password requirements