In affected versions of Octopus Deploy it is possible for a low privileged guest user to craft a request that allows enumeration/recon of an environment.

In affected versions of Octopus Deploy it is possible for a low privileged guest user to interact with extension endpoints.

In Octopus Deploy 2019.4.0 through 2019.6.x before 2019.6.6, and 2019.7.x before 2019.7.6, an authenticated system administrator is able to view sensitive values by visiting a server configuration page or making an API call.

In Octopus Deploy 2019.1.0 through 2019.3.1 and 2019.4.0 through 2019.4.5, an authenticated user with the VariableViewUnscoped or VariableEditUnscoped permission scoped to a specific project could view or edit unscoped variables from a different project. (These permissions are only used in custom User Roles and do not affect built in User Roles.)