Google's John Mueller said on Twitter "disavow the whole domain if you know there's an issue with some of its links." He said there is "no need to be exact when everything on a site is bad from your point of view." This reminds me of the advice from Matt Cutts to use the disavow link tool as a machete....
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Google Still Recommending Disavowing Whole Domains With Machete
seroundtable.com