---
title: "Data breach at Belnet"
description: "Belnet, the Belgian national research and education network, detected a security incident within its IT infrastructure on 24 September 2026, caused by the exploitation of a zero-day vulnerability in technology supplied by an external provider. Between 22 July and the morning of 25 September 2026, in"
canonical: https://inyourgeek.com/en/fuites-de-donnees/2026-09-29-belnet
type: fuite-de-donnees
author: "Sébastien Soulier"
publisher: "InYourGeek"
language: en
datePublished: 2026-09-29
dateModified: 2026-09-29
---
# Belnet

Data breach — Moderate

Belnet, the Belgian national research and education network, detected a security incident within its IT infrastructure on 24 September 2026, caused by the exploitation of a zero-day vulnerability in technology supplied by an external provider. Between 22 July and the morning of 25 September 2026, incoming emails sent to Belnet and one of its clients were copied by the attackers, along with their content and any attachments, to external infrastructure. The vulnerability was patched on 25 September at 08:10, and the Centre for Cybersecurity Belgium was brought in to assist the investigation.

The intercepted email content and attachments may reveal personal or professional information that could be used for targeted phishing attempts against the affected correspondents.

| Fact | Value |
| --- | --- |
| Disclosed on | September 29, 2026 |
| Incident dated | July 22, 2026 |
| Sector | Education |
| Country | Belgium |
| Cause | Misconfigured database |
| Severity | Moderate |
| Status | Confirmed |

## Exposed data

- Email address
- Employment data
- Other personal data

## 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

- [Belnet](https://frenchbreaches.com/alertes/belnet-munsqkj0sc95q8fxu2r) — FrenchBreaches
- [Security and privacy incident affecting Belnet's IT infrastructure](https://www.belnet.be/en/news-events/news/security-and-privacy-incident-affecting-belnets-it-infrastructure) — Belnet
- [La justice saisie après la cyberattaque de Belnet en Belgique](https://www.solutions-numeriques.com/la-justice-saisie-apres-la-cyberattaque-de-belnet-en-belgique/) — Solutions Numériques

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

---

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