Once again - if you *never* connect it online it doesn't matter how nastily infected it is (and physically disabling any ability for it to ever connect is my advice and what I have done to the old laptop I bought for this purpose).
Also don't use the OS on it either - use a LiveOS (and one that doesn't use the HDD).
To be paranoid, there may be an exploit to influence the RNG. But that's really paranoid.