# CVE-2026-9636

## Summary

- **CVE ID:** CVE-2026-9636
- **Severity:** HIGH
- **CVSS Score:** 8.2 (CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N)
- **CWE:** CWE-299
- **Published:** Jul 14, 2026
- **Last Modified:** Jul 14, 2026

## Description

A security issue exists within CompactLogix® 5380, ControlLogix® 5580, and EN4 communication modules related to CIP Security certificate revocation handling. The security issue stems from the controller failing to properly reject certificates signed by an intermediate certificate that has been revoked via a Certificate Revocation List (CRL). This could allow a network-based attacker to establish a connection using a certificate that should be untrusted, potentially bypassing CIP Security protections.

## Affected Products

- Rockwell Automation — ControlLogix® 5580, CompactLogix® 5380, GuardLogix® 5580, Compact GuardLogix® 5380, 1756-EN4TR (Version 36 - Version 37)

## References

- [CNA](https://www.rockwellautomation.com/en-us/trust-center/security-advisories/advisory.SD1788.html)

## Exploitation Prediction (EPSS)

- **EPSS Score:** 0.22%
- **EPSS Percentile:** 12.0

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_Exported from OnDuty AI Vulnerability Intelligence on 2026-09-10._