I know the following makes some assumptions based on evidence that does not exist at present, and may never turn up even if does exist, and may never exist at all. It's just my speculative thoughts on the situation and I'm not assuming anyone did anything... This is all as hypothetical to me as the Nazi's developing nukes in WW2. It's just a 'what if' type of thought.
Given the current tensions and military exercises, and lacking additional information to make decisions on, I can't help but wonder. Deliberate top down order and denial is an option, non-state individuals hacking or doing it as an inside job is possible, but it also could have been China... and if it was then its quite interesting. If there was enough technical proof this would be a nice textbook example of an offensive cyber-warfare psy-op. It has excellent social and political plausible deniability based on established elements, puts a time relevant psy-op relevant message into a targeted area in a way that gets the message in front of many people to achieve the desired psy-op goals. Pretty impressive and well executed if this is the case.
Given the current tensions and military exercises, and lacking additional information to make decisions on, I can't help but wonder. Deliberate top down order and denial is an option, non-state individuals hacking or doing it as an inside job is possible, but it also could have been China... and if it was then its quite interesting. If there was enough technical proof this would be a nice textbook example of an offensive cyber-warfare psy-op. It has excellent social and political plausible deniability based on established elements, puts a time relevant psy-op relevant message into a targeted area in a way that gets the message in front of many people to achieve the desired psy-op goals. Pretty impressive and well executed if this is the case.