How severe is CVE-2023-0027?

CVE-2023-0027 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2023-0027 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-0027?

CVE-2023-0027 affects Rockwellautomation Modbus Tcp Server Add On Instructions. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-0027?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2023-0027 published?

CVE-2023-0027 was published on 2023-03-17 and last updated on 2026-06-17.

CVE-2023-0027

CVE-2023-0027 is a medium-severity vulnerability in Rockwellautomation Modbus Tcp Server Add On Instructions with a CVSS 3.x base score of 5.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-200.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
EPSS exploit prediction: 1% (57th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-200
Affected product: Rockwellautomation Modbus Tcp Server Add On Instructions
Published: 2023-03-17
Last modified: 2026-06-17

Description

Rockwell Automation Modbus TCP Server AOI prior to 2.04.00 is vulnerable to an unauthorized user sending a malformed message that could cause the controller to respond with a copy of the most recent response to the last valid request. If exploited, an unauthorized user could read the connected device’s Modbus TCP Server AOI information.

Frequently asked questions

What is CVE-2023-0027?: Rockwell Automation Modbus TCP Server AOI prior to 2.04.00 is vulnerable to an unauthorized user sending a malformed message that could cause the controller to respond with a copy of the most recent response to the last valid request. If exploited, an unauthorized user could read the connected device’s Modbus TCP Server AOI information.
How severe is CVE-2023-0027?: CVE-2023-0027 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2023-0027 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-0027?: CVE-2023-0027 affects Rockwellautomation Modbus Tcp Server Add On Instructions. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-0027?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-0027 published?: CVE-2023-0027 was published on 2023-03-17 and last updated on 2026-06-17.

References

https://rockwellautomation.custhelp.com/app/answers/answer_view/a_id/1138766

Affected products (1)

cpe:2.3:a:rockwellautomation:modbus_tcp_server_add_on_instructions:*:*:*:*:*:*:*:*

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