CVE-2026-9636
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issue stems from the controller failing to properly reject certificates signed by an intermediate certificate that has been revoked via a Certificate Revocation List (CRL).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.
Scoring
- Severity
- HIGH
- CVSS base score
- 8.2
- CVSS vector
- 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
- EPSS probability
- 0.22%
- CWE
- CWE-299
- Published
- 2026-07-14
- Last modified
- 2026-07-14
Affected products
- Rockwell Automation ControlLogix® 5580, CompactLogix® 5380, GuardLogix® 5580, Compact GuardLogix® 5380, 1756-EN4TR
Weakness type
Related vulnerabilities
- CVE-2026-86231 — mwiede jsch KnownHosts.java getRevokedKeys improper check for certificate revocation
- CVE-2026-61699 — nebula-mesh: Certificate revocation is never enforced at the mesh
- CVE-2026-56821 — Netty: Out-of-date OCSP Responses Accepted by OcspServerCertificateValidator
- CVE-2026-6899 — Improper Check for Certificate Revocation in S2OPC
- CVE-2026-4428 — CRL Distribution Point Scope Check Logic Error in AWS-LC
- CVE-2025-11955 — Incorrect validation of OCSP certificates in TheGreenBow VPN Client Windows Enterprise
- CVE-2025-36057 — IBM Cognos Analytics Mobile (iOS) authentication bypass
- CVE-2025-3085 — MongoDB Server running on Linux may allow unexpected connections where intermediate certificates are revoked