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Everyday threatsChapter 6

Ransomware: before, during and after

How a ransomware attack unfolds, how to prepare, the first things to do, who to alert within 72 hours in France, and how to recover your business safely.

Belinda
Presented byBelinda
10 min readUpdated on 2 October 2026

What you will learn

  • How a ransomware attack unfolds, from initial access to double extortion
  • What French figures and a real case teach us
  • The defences that matter: backups, patching, MFA, segmentation, EDR
  • The first things to do, and the things to avoid
  • Who to alert in France and how fast: 17Cyber, CERT-FR, the police, your insurer, the CNIL
  • How to organise recovery and the lessons-learned review

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Chapter 1 is free to read. Chapters 2 to 21, like the Junior, Senior and Expert levels of the Cyber Quiz, are free too: all you need is a free KrakenShield account with a confirmed email address.

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Belinda

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