TI-2026-08477 Aliases CVE-2026-9653 GHSA-w8xr-7458-qr4m

1756-EN2, 1756-EN3, and 1756-ENBT - Denial of Service via CIP Connection ID

MEDIUM 43CWE-354Published 2026-07-14 · Updated 2026-07-14

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Attack requirements: None
Impact type: —
Confidentiality · integrity · availability: None · None · High
Fix status: No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00231 14th percentileScored 2026-11-07

Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: Yes
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
Rockwell	1756-EN2, 1756-EN3	up to 12.001	—	No fix listed	CNA
Rockwell	1756-ENBT	6.006	—	No fix listed	CNA

1756-EN2, 1756-EN3 VendorRockwell Affected up to 12.001 Fixed in — No fix listed CNA
1756-ENBT VendorRockwell Affected 6.006 Fixed in — No fix listed CNA

Remediation

No fixed version listed by the sources yet.

Timeline

2026-10-02 Threatist record created from CVE-2026-9653
2026-10-03 Alias added: GHSA-w8xr-7458-qr4m

References

Other 1

https://www.rockwellautomation.com/en-us/trust-center/security-advisories/advisory.SD1780.html

TI-2023-06904 Cisco is providing an update for the ongoing investigation into observed exploitation of… KEVCVSS 3.1CRITICAL 10.0
TI-2021-05574 Insufficiently protected credentials in Rockwell Automation Studio 5000 Logix Designer… KEVCVSS 3.1CRITICAL 9.8
TI-2023-02735 Rockwell Automation ThinManager Thinserver Software Vulnerable to Input Validation Vulnerability CVSS 3.1CRITICAL 9.8
TI-2023-02733 Rockwell Automation ThinManager Thinserver Software Vulnerable to Input Validation Vulnerability CVSS 3.1CRITICAL 9.1
TI-2010-02837 The WDB target agent debug service in Wind River VxWorks 6.x, 5.x, and earlier, as used… CVSS 3.1CRITICAL 9.8
TI-2023-12455 Rockwell Automation ThinManager ThinServer Path Traversal Download CVSS 3.1HIGH 7.5

See all 434 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences