puzio-saunierduval.fr Listed by lockbit5 Ransomware Group: Ransomware Claim — What’s Alleged & What To Do

On December 24, 2025, the domain puzio-saunierduval.fr was listed by the lockbit5 ransomware group. The listing states that internal files were exfiltrated during a ransomware attack, though the number of people affected and the precise contents of those files have not been disclosed. The practical stakes centre on the data held by a long-established heating and plumbing business. Customers, suppliers and staff may have records that include contact details, service histories or administrative information now outside the organisation’s control.

What happened

The incident was reported on December 24, 2025, when the domain appeared on a listing maintained by the lockbit5 group. The group claims that internal files were taken during a ransomware operation. No further details on the timing of the intrusion, the volume of data or the method of access have been made public. The organisation has not issued a statement confirming or denying the claims.

Who is lockbit5?

Lockbit5 is a ransomware group that has operated since at least 2019. It typically gains access through phishing, remote-desktop vulnerabilities or compromised credentials, then deploys encryption while also copying files. The group maintains a public site where it lists organisations it claims to have targeted, often releasing samples of data when ransom demands are not met. Its listings are unverified claims until independently confirmed by the affected organisation or law-enforcement agencies.

Who is puzio-saunierduval.fr?

Puzio-saunierduval.fr is the online presence of ETS PUZIO, a heating and plumbing company based in Chelles, France, that has operated since 1973. Businesses of this type routinely collect customer names, addresses, telephone numbers and service records, along with supplier contracts and internal administrative files. A breach at such an organisation can therefore involve data that spans many years of residential and commercial work.

The information in question

The listing refers only to “internal files exfiltrated in ransomware attack.” No specific categories of personal data have been published. Organisations in the heating sector commonly hold customer contact information, installation and maintenance records, and payment or contract details, but the exact contents of the exfiltrated material remain unconfirmed.

The real-world impact

Individuals whose records appear in the files may face an increased risk of unsolicited contact or attempts to use the information for fraud. The company itself may incur costs for investigation, system restoration and any regulatory notifications required under French or European data-protection rules. Because the scale of exposure is still unknown, the full extent of these consequences cannot yet be assessed.

Were you affected?

If you are a customer or former customer of ETS PUZIO, monitor your email and postal addresses for unexpected messages and review bank or payment statements for unusual activity. You can also run a free exposure scan of your email address against known breach data sets to check whether your information has appeared in previously published leaks. Contact the company directly for any official updates it may provide.

AICompiled with AI assistance from public sources and published under our editorial standards.