GHSA-53HJ-R94P-8C8F Kanidm has non-constant-time comparison of OAuth2 client_secret

Summary The kanidmd OAuth2 token-exchange /oauth2/token and token-introspection /oauth2/token/introspect endpoints compare the supplied clientsecret against the stored secret using Rust's PartialEq on String, which short-circuits on the first mismatching byte. This produces an observable timing...