This vulnerability (CVE-2026-0646) affects the 1794-AENTR adapter in Rockwell Automation's FLEX I/O EtherNet/IP Adapters product line, version 2.012. The issue is caused by missing release of memory after its effective lifetime during processing of CIP protocol requests, categorized under CWE-401 (Missing Release of Memory after Effective Lifetime). Exploitation results in denial-of-service by causing the adapter to fault and disconnect from associated I/O modules, necessitating manual intervention to restore operation. The CVSS v4.0 base score is 8.7, indicating high severity with network attack vector, no required privileges or user interaction, and high impact on availability.

Successful exploitation causes the 1794-AENTR adapter to fault and lose connectivity with its I/O modules, resulting in denial-of-service. This disrupts normal operation of the affected industrial control system components until a manual reset is performed. There is no indication of data confidentiality or integrity impact. No known exploits are reported in the wild at this time.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Since no official fix or temporary mitigation is provided, users should monitor Rockwell Automation advisories for updates. Until a patch is available, manual reset is required to recover from the fault condition caused by this vulnerability.