Rockwellautomation Micrologix Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

high Tenable.ot Plugin ID 500469
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Rockwell Automation MicroLogix 1400 Version 21.6 and below may allow a remote unauthenticated attacker to send a specially crafted Modbus packet allowing the attacker to retrieve or modify random values in the register. If successfully exploited, this may lead to a buffer overflow resulting in a denial-of-service condition. The FAULT LED will flash RED and communications may be lost. Recovery from denial-of-service condition requires the fault to be cleared by the user.


Refer to vendor advisory for Security Updates

See Also

Plugin Details

Severity: High

ID: 500469

Version: 1.0

Type: local

Family: SCADA

Published: 8/10/2021

Updated: 8/10/2021

Risk Information

CVSS Score Source: CVE-2021-22659


Risk Factor: High

Base Score: 7.5

Vector: AV:N/AC:L/Au:N/C:P/I:P/A:P


Risk Factor: High

Base Score: 8.6

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H

Vulnerability Information

CPE: cpe:2.3:o:rockwellautomation:micrologix_1400_firmware:*:*:*:*:*:*:*:*

Patch Publication Date: 3/25/2021

Vulnerability Publication Date: 3/25/2021

Reference Information

CVE: CVE-2021-22659