PatchSiren cyber security CVE debrief

CVE-2026-0646 Rockwell Automation CVE debrief

CVE-2026-0646 is a HIGH-severity denial-of-service vulnerability in the 1794-AENTR adapter. The issue arises from improper memory handling of CIP protocol requests, which can cause the adapter to fault and lose connection to its associated I/O modules. A manual reset is required to recover from this vulnerability. The Common Vulnerability Scoring System (CVSS) score for this vulnerability is 8.7.

Vendor: Rockwell Automation
Product: FLEX I/O EtherNet/IP Adapters
CVSS: HIGH 8.7
CISA KEV: Not listed in stored evidence
Original CVE published: 2026-06-16
Original CVE updated: 2026-06-16
Advisory published: 2026-06-16
Advisory updated: 2026-06-16

Who should care

Organizations using the 1794-AENTR adapter should prioritize patching this vulnerability to prevent potential denial-of-service attacks.

Technical summary

The vulnerability exists due to improper memory handling of CIP protocol requests in the 1794-AENTR adapter. This can result in the adapter faulting and losing connection to its associated I/O modules.

Defensive priority

HIGH

Recommended defensive actions

Apply the necessary patches or updates to the 1794-AENTR adapter as recommended by the vendor.
Review and implement secure configuration and operation practices for the adapter and its associated I/O modules.

Evidence notes

The CVE record and details were obtained from the official CVE.org and NVD sources.

Official resources

CVE-2026-0646 was published on 2026-06-16T15:16:33.567Z and modified on 2026-06-16T15:26:04.250Z.