Russian hackers have stolen hundreds of sensitive military documents containing details of eight RAF and Royal Navy bases as well as Ministry of Defence staff names and emails – and posted them on the dark web, The Mail on Sunday can reveal. In what has been described as a ‘catastrophic’ security breach, cybercriminals accessed the cache of files by hacking a maintenance and construction contractor used by the MoD. The ‘gateway’ attack – which targeted third party the Dodd Group – allowed cyber gangsters to circumvent the almost impenetrable cyber defences used by the Armed Forces. The MoD said it was investigating the enormous data and security breach, believed to have been carried out by Russian group Lynx. Leaked documents seen by the MoS disclose information about a number of sensitive RAF and Navy bases, including RAF Lakenheath, in Suffolk, where the US Air Force’s F-35 stealth jets are based and their nuclear bombs are believed to be housed.