Ice Ice Baby, a song from the album To the Extreme by Vanilla Ice published by Capitol Records. This was Vanilla's only number one hit.
The tune is based around a highly recognisable riff from the song Under Pressure by Queen and David Bowie. While "borrowing" and sampling are an acceptable part of the creation of modern music, doing so requires asking permission, acknowledging credit and paying royalties. Vanilla Ice did none of this.
There was no public court case over the issue but it seems inconceivable that the original copyright owners let the rapper get away with it; most likely there was some kind of settlement. Two years later Queen quietly asserted their moral rights in the liner notes of their Classic Queen compilation, stating "in 1990 the bass and piano featured again on Vanilla Ice's number one single Ice Ice Baby".
There is a hilarious clip of Vanilla Ice protesting the difference between the songs at the MTV website: