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.)

In affected versions of Octopus Deploy it is possible to perform a Regex Denial of Service via the package upload function.

In affected versions of Octopus Deploy it is possible to perform a Regex Denial of Service targeting the build information request validation.

In affected versions of Octopus Deploy it is possible to perform a Regex Denial of Service using the Variable Project Template.

In affected versions of Octopus Deploy it is possible to unmask sensitive variables by using variable preview.

In affected versions of Octopus Deploy it is possible for a user to view Tagsets without being explicitly assigned permissions to view these items

In affected versions of Octopus Deploy it is possible for a user to view Workerpools without being explicitly assigned permissions to view these items