# Belden HiOS Switch DoS Vulnerability Disclosed

Published: 2026-09-07 · Severity: routine · Sectors: infrastructure, manufacturing
Canonical: https://vorant.io/reports/4ff170ef-d270-54b1-aebc-7cfe5b813bb9/belden-hios-switch-dos-vulnerability-disclosed

> ANSSI advisory warns of a remote denial-of-service flaw in Belden HiOS Switch Platform firmware across multiple version branches.

ANSSI (CERT-FR) issued an advisory relaying a Belden PSIRT security bulletin describing a vulnerability in the HiOS Switch Platform, an industrial network switch firmware used in operational technology and industrial control environments. The flaw allows a remote attacker to trigger a denial-of-service condition, potentially disrupting network switching functionality on affected devices. No CVE identifier was provided in this advisory, and no indication of active exploitation was given.

The vulnerability affects a broad range of HiOS firmware versions across the 07.x, 08.x, 09.0.x, 09.3.x, 10.3.x, and 10.5.x branches, all prior to specific patched releases. Given HiOS's use in industrial and infrastructure networking equipment, organizations operating Belden switches should consult the vendor's PSIRT bulletin and apply the corresponding firmware updates to mitigate the risk of service disruption.

Source reporting: https://www.cert.ssi.gouv.fr/avis/CERTFR-2026-AVI-1126

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