CVE-2020-9307: Belden Hirschmann Hios

Medium severity, CVSS 6.5. EPSS: 0.6% chance of exploitation in the next 30 days.

Hirschmann OS2, RSP, and RSPE devices before HiOS 08.3.00 allow a denial of service. An unauthenticated, adjacent attacker can cause an infinite loop on one of the HSR ring ports of the device. This effectively breaks the redundancy of the HSR ring. If the attacker can perform the same attack on a second device, the ring is broken into two parts (thus disrupting communication between devices in the different parts).

Affected products

  • Belden Hirschmann Hios: from 07.0.04, before 07.1.00 (fixed in 07.1.00); from 08.0.00, before 08.3.00 (fixed in 08.3.00)

Published 2021-02-11. Last modified 2026-06-17.