CVE-2026-84235: Rockwell Automation 1756-ENBT Denial of Service Vulnerability

Published Sep 1, 2026

Updated

A denial-of-service security issue exists in the affected product. The security issue stems from a crafted CIP packet being sent crashing the module. The device requires a restart to recover.

Affected Software

1 affected component

Rockwell Automation 1756-ENBT

Remediation

Recommended actions to resolve this vulnerability, in priority order.

Upgrade
Upgrade Rockwell Automation 1756-ENBT to a version that resolves this vulnerability.
Fixed in 1756-EN2T
Operational
Restart the affected 1756-ENBT module to recover from the denial-of-service condition.

Event History

Sep 1, 2026

CVE Published

via MITRE·01:07 PM

Data Sourced

via MITRE·01:07 PM

RemedyDescription

Frequently Asked Questions

What does an attacker need to do to trigger the issue?

The attacker must send a crafted CIP packet to the affected module.

How is service restored after the module crashes?

The device requires a restart to recover.