The Chinese government is apparently sophisticated enough to hack into Marriott's reservation system, yet - just like the Russian "hack" of the DNC - reportedly left behind evidence of "hacking tools, techniques and procedures" pointing to Beijing as the culprit, according to Reuters, citing three anonymous sources with knowledge of a private internal investigation. 

The hack which began four years ago exposed the records of up to 500 million customers in the Starwood hotels reservation system - now owned by Marriott, and "suggests that Chinese hackers may have been behind a campaign designed to collect information for use in Beijing's espionage efforts and not for financial gain." 

Along with the news that Huawei's CFO was arrested at the behest of the US, the timing of this announcement certainly puts a damper on whatever headway Trump and his administration have been making on trade with Beijing. In fact, as Reuters conveniently points out: 

Wait, it could have been anybody?

Reuters notes in the fourth paragraph that while China is the prime suspect in the case, "the sources cautioned it was possible somebody else was behind the hack" since "other parties had access to the same hacking tools, some of which have previously been posted online." 

Further complicating matters is the fact that "investigators suspect multiple hacking groups may have simultaneously been inside Starwood's computer networks since 2014," according to one of the sources. 

In short, Reuters' headline reads: "Clues in Marriott hack implicate China" while their article then admits it literally could have been anyone. 

We also know from the WikiLeaks "Vault 7" release of CIA hacking tools that the US government, among others, has the ability to misdirect attribution to foreign actors by leaving behind the "fingerprints" of the groups that the attack techniques were stolen from.