UK Technology Secretary Kendall and Security Minister Jarvis publish open letter: Mythos is 'substantially more capable at cyber offence than any model we have previously assessed'
Technology Secretary Liz Kendall and Security Minister Dan Jarvis issued a joint open letter to UK business leaders warning that AI models — citing Mythos specifically — are 'becoming capable of doing work that previously required rare expertise: finding weaknesses in software, writing the code to exploit them.' The letter cited the AISI's finding that frontier model capabilities are now doubling every four months rather than every eight, and called on businesses to prioritize cybersecurity at board level.
A cabinet-level joint ministerial letter naming Mythos as the most capable offensive model the AISI has ever assessed is the UK government's highest-level public policy escalation since the model was announced, placing Mythos explicitly in the UK's national cybersecurity governance agenda.