the requests are coming from the computers outside of china (that access chinese sites), thus you cannot simply BGP null-route all Chinese prefixes to mitigate this.
Re:China's Man-On-the-Side Attack on GitHub
by peteretep on Tuesday March 31, 2015 @01:38AM
(#9294565)
> I thought it was only people outside China who are being
> giving the poisoned javascript, and the requests are
> being made on the client-side from them - which would
> appear to be just random traffic
I would have thought you could usefully heuristically look at the referrer header.
Perhaps Baidu still shows up as the referring URL, though?