---
title: "Data breach at Zenfirst (édité par DUOSQUADRA)"
description: "A data leak affecting Zenfirst, a French invoicing and cash-management software published by Bordeaux-based DUOSQUADRA, was claimed on a cybercriminal forum on 17 September 2026. The poster claims to be releasing data on roughly 4,390 user accounts along with a batch of business customers' invoices."
canonical: https://inyourgeek.com/en/fuites-de-donnees/2026-09-17-zenfirst-edite-par-duosquadra
type: fuite-de-donnees
author: "Sébastien Soulier"
publisher: "InYourGeek"
language: en
datePublished: 2026-09-17
dateModified: 2026-09-17
---
# Zenfirst (édité par DUOSQUADRA)

Data breach — Moderate

A data leak affecting Zenfirst, a French invoicing and cash-management software published by Bordeaux-based DUOSQUADRA, was claimed on a cybercriminal forum on 17 September 2026. The poster claims to be releasing data on roughly 4,390 user accounts along with a batch of business customers' invoices. Samples reviewed by several specialized outlets show names, email addresses, phone numbers, company details and invoice information (amounts, taxes, due dates, invoice numbers). Zenfirst has not publicly confirmed the incident at this stage.

The combination of personal contact details with company and invoicing information could support targeted phishing attempts impersonating Zenfirst or its business customers.

| Fact | Value |
| --- | --- |
| Disclosed on | September 17, 2026 |
| Accounts affected | 4,390 |
| Sector | Digital services |
| Country | France |
| Cause | Undisclosed |
| Severity | Moderate |
| Status | Reported |

## Exposed data

- Email address
- Full name
- Phone number
- Employment data
- Customer ID
- Order history

## What you can do

- Expect phishing attempts quoting your name and this company. A message that knows your details is not legitimate for that reason.
- You can ask the organisation exactly what was exposed about you (right of access), and complain to the DPA if no answer comes within a month.

## Sources

- [Zenfirst](https://frenchbreaches.com/alertes/zenfirst-mu5htqiwd1qoi6ixtx5) — FrenchBreaches
- [Zenfirst : fuite de données revendiquée visant 4 390 utilisateurs](https://fuitesinfos.fr/article/2026-09-17-zenfirst) — Fuites Infos
- [Zenfirst Dataset Claim Includes User, Lead and Invoice Records](https://darkwebinformer.com/zenfirst-dataset-claim-includes-user-lead-and-invoice-records/) — Dark Web Informer
- [French Management Software Provider Zenfirst Suffers Data Breach Exposing 4,400 User and Invoice Records](https://www.brinztech.com/breach-alerts/brinztech-alert-french-management-software-provider-zenfirst-suffers-data-breach-exposing-4400-user-and-invoice-records) — Brinztech
- [Zenfirst victime d'une cyberattaque : des milliers de données de facturation exposées](https://www.cyberattaque.org/zenfirst-victime-dune-cyberattaque-des-milliers-de-donnees-de-facturation-exposees/) — Cyberattaque.org
- [[FR] zenfirst.fr – 4.4K](https://hacknotice.com/2026/09/17/fr-zenfirst-fr-4-4k/) — HackNotice

_Entry built from the cited sources after a corroboration check, then reviewed before publication._

---

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