Vulnerability · Published Jul 14, 2026 · Assigned by Rockwell
CVE-2026-96531756-EN2, 1756-EN3, and 1756-ENBT - Denial of Service via CIP Connection ID
High 8.7
In plain English
A high-severity security flaw in 1756-EN2, 1756-EN3 from Rockwell Automation. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 14% of all known vulnerabilities).
Official description
A denial-of-service security issue exists across all the 1756-EN2, EN3, and ENBT communication module due to improper validation of CIP Implicit Connection packets. An attacker on the network can exploit this by sending crafted packets to continuously disrupt device connections, though device connections will recover immediately after.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Rockwell Automation | 1756-EN2, 1756-EN3 | 12.001 and before |
| Rockwell Automation | 1756-ENBT | 6.006 |
Weakness: CWE-354 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N