CVE-2023-38744

7.5 HIGH 0.9% exploit odds Fix listed

What it is

Denial-of-service (DoS) vulnerability due to improper validation of specified type of input issue exists in the built-in EtherNet/IP port of the CJ Series CJ2 CPU unit and the communication function of the CS/CJ Series EtherNet/IP unit. If an affected product receives a packet which is specially crafted by a remote unauthenticated attacker, the unit of the affected product may fall into a denial-of-service (DoS) condition. Affected products/versions are as follows: CJ2M CPU Unit CJ2M-CPU3[] Unit version of the built-in EtherNet/IP section Ver. 2.18 and earlier, CJ2H CPU Unit CJ2H-CPU6[]-EIP Unit version of the built-in EtherNet/IP section Ver. 3.04 and earlier, CS/CJ Series EtherNet/IP Unit CS1W-EIP21 V3.04 and earlier, and CS/CJ Series EtherNet/IP Unit CJ1W-EIP21 V3.04 and earlier.

At a glance

Exploitability: Can be exploited over the network without logging in. High risk of service disruption.
Exploit odds: 0.9% chance of exploitation in the next 30 days (EPSS).
Fix: A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

2023-08-03 05:15 UTC PublishedDisclosed publicly on CVE.org and NVD
2026-06-17 06:11 UTC Last updatedMost recent change to the record

Why it ranks here

Exploited in the wild: no, CISA does not list it.
Exploit odds: 0.9% in the next 30 days (EPSS).
Severity: 7.5 HIGH (CVSS).
Fix: a patch or advisory is linked.

Details

Published: 2023-08-03 05:15 UTC
Last modified: 2026-06-17 06:11 UTC
Exploit probability: 0.9% · EPSS, next 30 days
Weakness: CWE-1284
Record status: Modified

Affected

Omron cj2m-cpu35 Firmware ≤ 2.18
Omron cj2m-cpu34 Firmware ≤ 2.18
Omron cj2m-cpu33 Firmware ≤ 2.18
Omron cj2m-cpu32 Firmware ≤ 2.18
Omron cj2m-cpu31 Firmware ≤ 2.18
Omron cj2h-cpu68-eip Firmware ≤ 3.04
Omron cj2h-cpu67-eip Firmware ≤ 3.04
Omron cj2h-cpu66-eip Firmware ≤ 3.04

Attack profile CVSS 3.1 · 7.5

Attack vector: Network
Complexity: Low
Privileges needed: None
User interaction: None
Scope: Unchanged
Confidentiality: None
Integrity: None
Availability: High

Raw vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Is it in your code?

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Fix and advisories

References

NVD record · CVE.org record