CVE-2026-9653

Rockwell Automation 1756-EN2, 1756-EN3VulnerabilityCVSS 8.7

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.

No public exploitation has been reported so far. No distribution fix is listed yet; apply vendor mitigations and monitor.

Recommended action: Track your distribution's security tracker and apply the fix as soon as it ships.

CVE-2026-9653 Rockwell Automation 1756-EN2, 1756-EN3 Vulnerability

Severity metrics

CVSS 4.0 : 8.7 HIGH

Attack vectorNetwork (remote)

Attack complexityLow

Attack requirementsNone

Privileges requiredNone

User interactionNone

Confidentiality impactNone

Integrity impactNone

Availability impactHigh

Subsequent confidentialityNone

Subsequent integrityNone

Subsequent availabilityNone

Vector: AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Affected & fixed versions by distribution

Versions are the native distribution strings (backport-aware): RHEL/Debian/SUSE backport fixes, so compare with the distro version comparator (dpkg / rpm / vercmp), not the upstream version.

No affected package in the tracked watchlist yet (Debian, Ubuntu, Arch, SUSE, Red Hat...). Triage may still be pending.

Sources

Advisory NVD CVE.org

Published 2026-07-14 · updated 2026-07-26 · source: NVD