Vulnerability · Published Apr 3, 2026 · Assigned by VulnCheck

CVE-2020-37216Hirschmann HiOS EtherNet/IP Stack Denial of Service

High 7.5

In plain English

A high-severity improper input validation in Hirschmann HiOS from Belden. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.9% (higher than 61% of all known vulnerabilities).

Severity (CVSS 3.1)7.5High

Exploit odds (30 days)0.9%top 39.0% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

Hirschmann HiOS devices versions prior to 08.1.00 and 07.1.01 contain a denial of service vulnerability in the EtherNet/IP stack where improper handling of packet length fields allows remote attackers to crash or hang the device. Attackers can send specially crafted UDP EtherNet/IP packets with a length value larger than the actual packet size to render the device inoperable.

Affected products (as reported)

Vendor	Product	Versions
Belden	Hirschmann HiOS	05.00.00 – through 08.0.00

Weakness: CWE-20 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References

https://assets.belden.com/m/3d3e2cbfa4860258/original/Belden-Security-Bulletin-BSECV-2019-14.pdf vendor-advisory
https://www.vulncheck.com/advisories/hirschmann-hios-ethernet-ip-stack-denial-of-service third-party-advisory