Whitehall Data Breach Gave Secrets to Chinese
16th October 2025
hina obtained “vast amounts” of classified government information over a period of many years by compromising a network used to transfer data across Whitehall.
Dominic Cummings, who served as a senior adviser to Boris Johnson, said that he and the then prime minister were informed about the breach in 2020 but that there had subsequently been a cover-up.
He said he was warned at the time that disclosing some specific details of the breach would be a criminal offence. He claimed that the breach included some “Strap” material, which is the government term for the highest level of classified information.
The breach, which was confirmed by two other senior Whitehall sources, was said to have been connected to a Chinese-owned company involved in Britain’s critical national infrastructure. Tom Tugendhat, a former Tory security minister, supported Cummings’s account.