Paris (France) (AFP) – Up to ten times a day, Sébastien publishes an almost identical message on

Published on: 09/30/2026 - 10:11

In August, on the eve of its formalization by the Ministry of the Economy, he notably warned of a major leak of tax data.

Like Sébastien, alias Seblatombe, and his site FrenchBreaches, several accounts have been created in recent months to take inventory of data thefts. They are increasing their publications, at the risk of attracting some criticism from the cybersecurity sector.

“We have several tools that scan various cybercriminal forums on the dark web,” where hackers claim responsibility for their attacks, explains Sébastien, who does not wish to use his last name.

Thomas Lazzaroni, behind the website cyberattack.org, also explains that he monitors "alerts on networks, notably Facebook, where small structures, town halls, associations (...) communicate".

“I don’t sleep much anymore,” he quips, referring to the increase in data thefts over the past several years, and the time spent spotting them.

Inform the general public

These volunteers have varied backgrounds. Thomas Lazzaroni works in the marketing department of a tech company, Sébastien defines himself as a “self-taught” cyber specialist, and indicates on his site that he specializes in “digital protection” in the music industry, without further details.

Christophe Boutry, followed by 20,000 subscribers on

They all have the same ambition: to inform the general public.

For Aeris, campaigner for the protection of personal data and creator of the pioneering site bonjourlafuite.eu.org in early 2024, it is also about “trying to raise awareness”.

But the methods of these bloggers, some of whom claim to be "whistleblowers", also give rise to reservations.

“Obviously there is also a need for committed citizen actors who participate in raising awareness, in alerting if necessary” but “we must pay attention, obviously, to the ethical nature of all that,” declared the director general of the National Information Systems Security Agency (Anssi) Vincent Strubel at the beginning of March.

In 2025, more than half of the alerts received by the institution on data leaks were unproven, according to Mr. Strubel.

Race to publication

Faced with criticism, cyber influencers claim a certain experience. “There are certain hackers that we are starting to know, we know their reputation and the fact that they have not cheated on previous claims,” explains Thomas Lazzaroni.

Another stage of their verification work: consultation of extracts from the databases, often published by pirates to support their allegations.

With FrenchBreaches, Sébastien also regularly contacts Anssi and companies allegedly targeted by pirates.

“He actually warned us of the claim of the famous hacker, who had not informed us, so it went rather well,” testifies the head of one of these organizations, contacted by AFP.

Their method is not completely foolproof, however. Another organization, which also wished to remain anonymous, indicates that the first elements published were inaccurate. They were then amended on the FrenchBreaches website.

The other sensitive point lies in whether or not to communicate with the pirates.

If Sébastien assumes to discuss with them, to "ask for certain information", and has already published interviews with some of these actors, Thomas Lazzaroni assures that he speaks to them "very little".

“I am also contacted by hackers who send me their data theft directly, but I refuse to highlight their crimes,” says Aeris.

Others also point out certain abuses. “There is a kind of race for publication, for the one who will publish the fastest on a leak which has been claimed (...) but it is also done to the detriment of information and quality”, describes Christophe Boutry.

© 2026 AFP

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