OpenAI has been briefing federal agencies, state governments and Five Eyes allies on the capabilities of its new cyber product over the past week, Axios has learned. Why it matters : Companies and agencies are clamoring to get their hands on the latest AI tools, whose advanced cybersecurity capabilities promise big gains for defenders and frightening advances for malicious hackers. Driving the news : OpenAI held an event in D.C. on Tuesday for approximately 50 cyber defense practitioners across the federal government to demo the capabilities of its new GPT-5.4-Cyber model, which it rolled out under a tiered access program last week. Government applicants are going through the same vetting process as commercial customers who wish to join its Trusted Access for Cyber program, a source familiar said. Attendees included a range of officials from across the government and national security agencies, most of whom oversee day-to-day cyber tasks.…