Police union Alliance warns members that an intruder accessed their data

The letter has a neutral title: “Information regarding the protection of your data.” Its content is less so. Alliance Police Nationale, one of France's main police unions, warns its members that a third party may have accessed some of their personal data.

The incident was made public on October 24 by the site Cyberattaque.org, which obtained a copy of the letter, and was then picked up by Clubic, Fuites Infos and Police & Réalités. The union refers to “unauthorized access to certain personal data.” It says it has launched investigations with specialists to find the origin of the incident, assess its consequences and strengthen its protections.

How many officers, and what data?

The letter does not say. It does not specify the number of members affected, the date of the intrusion or the nature of the information accessed. It is also unknown whether any files were copied.

With no answer, specialist media turned to the union's 2026 membership form. According to Police & Réalités, it asks for name, date and place of birth, home address, email and phone number, but also career details: service number, rank, city and unit of assignment, seniority, and status as a judicial police officer. Members who pay by direct debit may have provided a SEPA mandate and bank details (RIB). Nothing confirms at this stage that these fields were among the data accessed.

One thing is certain: a union file inherently reveals each person's union membership. The European data protection regulation (GDPR) makes it a special, so-called sensitive, category. When a breach poses a risk to individuals, the data controller must in principle notify the CNIL (the French data protection authority), if possible within 72 hours; if the risk is high, it must also inform the people concerned. The letter does not mention the CNIL.

Who is behind it?

No claim of responsibility had been spotted as of October 24, according to Cyberattaque.org. A few days earlier, the group Dark Storm had claimed to have knocked the union's website offline with a denial-of-service attack, as part of a wave targeting several French services. The media following the story stress that no link has been established between the two events.

This is not the union's first alert. In December 2018, a site used to manage transfer requests was hacked and the data of nearly 500 police officers was published. The DGSI (France's domestic intelligence agency) was put in charge of the investigation. Nothing indicates that the current incident is related to that one.

Best practices for members

There is no need to know the extent of the leak to protect yourself: the main danger is a message or call that seems credible because it contains real information. The union itself urges vigilance against emails, text messages and calls asking for personal or banking information.

• A caller who cites your rank or assignment is not necessarily legitimate. If they ask for bank details or a code, hang up and call the union back at a number you already know.
• Be wary of messages impersonating Alliance, your administration, your human resources department or your bank.
• Monitor your bank statements if you pay your dues by direct debit.
• For police officers, an exposed home address is a harassment risk: report any unusual contact to your superiors.

Files of activist organizations have become a regular target in recent weeks, as shown by the leak of the Communist Party's membership file. For Alliance, the next step is up to the union: finally say how many members are affected and what the intruder was able to see.