Vase Bug leaning tower of Pisa

This bug is odd.
Vase printing an open top and bottom square cube with a 2mm brim around base.
This prints inconsistently like the leaning tower of Pisa but only in the Y axis so far.
I have looked at the sliced gcode line by line and all the corners have identical vertical X and Y values.
My guess is this another artifact of the software rounding tool chain bug.