They definitely played with the NGSS setting for Long distance & soft distance shadows and increased that. For me soft shadow at about 0.02 & long shadow at 1.5 with the first 2 sampling settings set to max get a similar effect to this one. Beyond this, you can modify yourself inside the NGSS the noise image used.
You can even see on this one below the boobs the noise image - it's the default one. The sampling is just very high(32 & 64, first 2 NGSS settings).
T
