CVE-2023-3596Rockwell Automation Allen-Bradley ControlLogix Communication Modules vulnerable to Denial of Service
- 7.5HighCVSS base score
- 3.7%Exploitation in 30 daysEPSS · top 10% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
Where this vulnerability exists in the Rockwell Automation 1756-EN4* Ethernet/IP communication products, it could allow a malicious user to cause a denial of service by asserting the target system through maliciously crafted CIP messages.
Timeline
ID reserved
By Rockwell
- 2 days later
· 2 days later
Published
- 16 months later
· 16 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| RockwellCNA (assigner) | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVDNVD · Modified | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 3.7% · top 10% of all CVEs (13 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.5.
Affected products
Rockwell Automation · 1756-EN4TR Series A
- affected <=5.001
Rockwell Automation · 1756-EN4TRK Series A
- affected <=5.001
Rockwell Automation · 1756-EN4TRXT Series A
- affected <=5.001
What to do
Solution: * Update firmware. Update EN4* ControlLogix communications modules to firmware revision 5.002. * Properly segment networks. Given a cyber actor would require network connectivity to the communication module to exploit the vulnerability, organizations should ensure ICS/SCADA networks are properly segmented within the process structure as well as from the Internet and other non-essential networks. * Implement detection signatures. Use appended Snort signatures to monitor and detect anomalous Common Industrial Protocol (CIP) packets to Rockwell Automation devices.
References
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2023-44246 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2023-3596)Record last updated .