Yahoo Music Unlimited hacked already?

Nobody seems to be very forthcoming about how exactly this is done, but Robert Chapin reports that his company,
Chapin Information Services, has discovered an exploit in the Yahoo website that allows an individual to download DRM-free tracks from the Yahoo Music Unlimited service without ever having paid for them. All that is known about the technology behind the hack is that you don't "have to be a technical genius" to do it. Apparently, Chapin has been trying without success to contact Yahoo and inform them about the exploit, and has received all of a two sentence email in response. The hack appears to be the result of some design flaw in the Yahoo website, but it looks like we're just gonna have to wait out the knowledge on how to, um, continue these security tests for ourselves.

[Via GigaOm]