CVE-2020-37216 Belden CVE debrief

Who should care

Security teams responsible for Hirschmann HiOS devices should prioritize patching to prevent potential denial of service attacks. Network administrators and IT professionals managing critical infrastructure that relies on these devices should be aware of the vulnerability and take necessary precautions. Industrial control system operators and cybersecurity teams should review their systems for potential exposure and implement compensating controls if necessary.

Technical summary

The CVE-2020-37216 vulnerability affects Hirschmann HiOS devices versions prior to 08.1.00 and 07.1.01. The EtherNet/IP stack improperly handles packet length fields, allowing remote attackers to crash or hang the device. The vulnerability can be exploited by sending specially crafted UDP EtherNet/IP packets with a length value larger than the actual packet size. This issue is particularly concerning for industrial control systems and critical infrastructure, where device availability is crucial.

Defensive priority

High

Recommended defensive actions

• Apply patches or updates to Hirschmann HiOS devices to version 08.1.00 or later, or 07.1.01 or later.
• Implement network segmentation to limit access to vulnerable devices.
• Monitor network traffic for suspicious activity.
• Conduct regular vulnerability assessments and penetration testing.
• Review compensating controls for exposed systems while remediation is scheduled and verified.
• Check relevant monitoring, detection, and logs for exposed assets that need extra review.
• Track exceptions, retest remediated assets, and close the item only after evidence is documented.

Evidence notes

The CVE record was published on 2026-04-03T21:17:08.213Z and has not been modified since then. The NVD entry is currently Awaiting Analysis. The vulnerability has a CVSS score of 8.7 and is classified as HIGH severity. The evidence is limited to publicly available information and may not reflect the full scope of affected systems or potential impacts.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.