First things first: this is the biggest leak of secret American information on the war in Ukraine since Russia's full-scale invasion 14 months ago. Some of the documents are as much as six weeks old, but the implications are huge.
Pentagon officials are quoted as saying the documents are real.
Information on at least one of them appears to have been crudely altered in a later version, but out of a dump of as many as 100 documents, that seems a relatively minor detail.