Before playback starts, all the devices involved are checked using a hardware functionality scan (HFS) to verify if they are genuine and have not been tampered with.
The report also concluded in tests involving real world applications Vista performed considerably slower, noting "We are disappointed that CPU-intensive applications such as video transcoding with Xvi D (DVD to Xvi D MPEG4) or the Main Concept H.264 Encoder performed 18% to nearly 24% slower in our standard benchmark scenarios".
Other commonly used applications, including Photoshop and Win RAR, also performed worse under Vista.
The result of this is that any already existing buffer overflow bugs that, in Vista, were previously not exploitable due to such features, may now be exploitable.
This is not in itself a vulnerability: as Sotirov notes, "What we presented is weaknesses in the protection mechanism.
A subset of the benchmarks used were provided by Standard Performance Evaluation Corporation (or SPEC), who later stated that such "results should not be compared to those generated while running Windows XP, even if testing is done with the same hardware configuration." SPEC acknowledges that an apple-to-apples comparison cannot be made in cases such as the one done by Tom's Hardware, calling such studies "invalid comparisons." However, the Toms Hardware report conceded that the SPECviewperf tests "suffered heavily from the lack of support for the Open GL graphics library under Windows Vista".