I feel sorry for the poor people of the UK.
When I saw the title of the news item announcing Russia and China had decrypted Snowden's encryption, I immediately read the article because I keep current on Snowden's ongoing story, and, knowing what I do about cryptography and Snowden, it looked unbelievable. But the prominence of the article implied the editors were giving it a stamp of approval.
But sure enough, when I read it, there was nothing. And anybody with even a mildly critical eye would say the same. The story is about an anonymous source claiming the ridiculous at a convenient time. So the question now isn't about the details of the article. Even the authors (Tom Harper, Richard Kerbaj and Tim Shipman) of the article knows it's about nothing. The question is why did the editors of The Sunday Times and everybody else publish obvious nothing?
Answer: In my life, I've learned when you see something that doesn't make sense on the surface, then there must be something beneath. And usually, it's money.
In this case, the situation is doubtless more complicated than direct cash for lies, but it amounts to the same. The Guardian has a decent article: http://www.theguardian.com/us-news/2015/jun/14/russia-and-china-broke-into-snowden-files-to-identify-british-and-us-spies