type: incident · created: 2026-09-09 · updated: 2026-09-09 · tags: [incident, law-enforcement, tax, breach, zerobytes, france] · confidence: high · affected_sectors: [government, finance] · au_impact: false
French Prosecutors Confirm Arrest of Suspected ZeroBytes Hacker Behind Tax Cyberattack
The Paris prosecutor's office confirmed the arrest of an 18-year-old suspected member of the French-speaking ZeroBytes hacking group, detained 18 August and placed in pretrial detention over attacks on the French tax authority DGFiP and other organisations; a second suspect under 16 was arrested 26 August and released while investigators examine his devices.
| Attribute | Detail |
|---|---|
| Suspect | 18-year-old, alias "ChatNoir" |
| Charges | Organised unauthorised access, data theft, refusing to provide a decryption key (up to 10 years) |
| Prior cases | 2024 breach of French telecom Free (~19 million customers) |
| DGFiP impact | 600,000+ people potentially exposed (data stolen late June) |
| Source | The Record — Tier 2/4 |
The 18-year-old was already under judicial supervision in two earlier cases, including the 2024 Free breach. DGFiP disclosed in August that data on more than 600,000 people may have been exposed.