The primary source, and short enough that every product owner should read it once themselves. From 11 September 2026, manufacturers must report actively exploited vulnerabilities and severe security incidents. Early warning within 24 hours, full notification within 72, final report no later than 14 days after a corrective measure is available. The part that gets underestimated: the clock starts once a prompt initial assessment gives you reasonable certainty, and the Commission expects that assessment immediately, not at your next release date. Anyone without a process that produces a first report inside one working day does not have a future compliance problem. They have one from September.