Tax hack: What we know about the cyberattacks on French government agencies

Cover image: A woman walks near the French Economy and Finance Ministry building known as Bercy along the River Seine in Paris, France, August 11, 2026. © Sarah Meyssonier, Reuters

French government systems came under attack by hackers who stole information on hundreds of thousands of households and private businesses in June and July, notably from the tax authority. Here's what we know about the latest cyberattacks, and what the government is doing to keep personal information secure.

Cyber hackers have stolen detailed financial information on hundreds of thousands of individuals and companies from tax and land registry computers, French authorities admitted on August 14.

France's Public Finance agency (DGFiP), which oversees the tax system, said there were two separate cyber attacks on its computers. Details from more than 678,000 individual and professional accounts were taken in the first hack in June, with names, "income reference data" and tax rates paid among the details taken. The second theft in July concerned details on 200,000 land registry accounts.

The agency's head, Amélie Verdier, ​said Tuesday that another data breach was detected on Monday that ⁠is still being evaluated.

Cover image: En esta foto tomada el 5 de marzo de 2015, los empleados trabajan en la sede de Bitdefender, una empresa líder rumana en ciberseguridad, en Bucarest, Rumanía. Rumanía, el país de Europa del Este, conocido más por su desorden económico que por su destreza tecnológica, se ha convertido en una de las principales naciones europeas en la lucha contra el hacking. La razón: la propia lucha del país contra los renegados de Internet y un legado de excelencia informática derivado del régimen del dictador comunista Nicolae Ceaușescu. © Octav Ganea, AP

The thefts were claimed on a dark-web forum by ZeroBytes, a self-proclaimed French hacking duo that said they had access to a VPN used by tax officials.

Contacted by AFP and asked about motives, the duo said they had no "particular motivation" before adding: "money, I imagine". They said the stolen information had already been sold to "two people" for "thousands of euros".

The duo claim to have details on 250,000 land registry accounts involving about 2 million people who own land and property in France.

On Monday, the group said they also obtained information on millions of students and tens of thousands of teachers, some of it dating back 20 years.

Experts say France is one of the countries most targeted by cybercriminals.

Read moreFrench state services hit by cyberattacks of 'unprecedented intensity'

Prime Minister Sébastien Lecornu on Wednesday asked the National Cybersecurity Agency to set up a new "cyber unit" to counter cyberattacks.

Budget ​Minister David ​Amiel said on Tuesday that his ministry will ​use ‌artificial intelligence tools ⁠to test the cybersecurity vulnerabilities of government ‌agencies following last week's disclosure. He stressed that the government would only work with what he described as "sovereign" AI providers – such as France's Mistral – and explicitly excluded US-based OpenAI.

France's identity document agency ANTS was hit by a massive attack in April affecting the data of nearly 12 million individuals and professionals.

In February, the finance ministry said that a large-scale breach of its computer system had resulted in the theft of the details of 1.2 million bank accounts. Days later, hackers stole the medical information of some 15 million individuals.

(FRANCE 24 with AFP and Reuters)