After test execution with MITK_VTK_DEBUG_LEAKS turned ON in the superbuild:

[...]
vtkDebugLeaks has detected LEAKS!
Class "vtkCurvatureMeasure" has 1 instance still around.
Class "vtkIsotropicDiscreteRemeshing" has 1 instance still around.
Class "vtkObject" has -26 instances still around.
Class "vtkSinglePolynomialMeasure" has 12 instances still around.
Class "vtkIdList" has 1 instance still around.
Class "vtkNeighbourhoodComputation" has 12 instances still around.

http://cdash.mitk.org/testDetails.php?test=9334942&build=498015

If it is not easily fixable it can be turned of with

vtkDebugLeaks::SetExitError(0);

in the test, see recent changes in Modules/PlanarFigure/Testing/mitkViewportRenderingTest.cpp for an example