So what if you can measure a voltage? Without also measuring the source impedance, you have no grounds whatsoever to claim that the product is actually or potentially harmful.
It's current through the human body that's harmful. Put your multimeter in AC current mode, and measure between the case of the computer and earth. Let us know, quantitatively, what you measure.
It's very common indeed to have a high - but not infinitely high - impedance path between the primary and secondary sides of a PSU. Provided, that the leakage current is lower than that prescribed by the applicable safety standard, there is no issue.