Schneider Electric Modicon Authentication Bypass by Spoofing (CVE-2018-7842)

critical Tenable OT Security Plugin ID 500122


The remote OT asset is affected by a vulnerability.


A CWE-290: Authentication Bypass by Spoofing vulnerability exists in all versions of the Modicon M580, Modicon M340, Modicon Quantum, and Modicon Premium which could cause an elevation of privilege by conducting a brute force attack on Modbus parameters sent to the controller.

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Refer to the vendor advisory.

See Also

Plugin Details

Severity: Critical

ID: 500122

Version: 1.3

Type: remote

Family: Tenable.ot

Published: 2/7/2022

Updated: 8/22/2023

Risk Information


Risk Factor: Medium

Score: 6.7


Risk Factor: High

Base Score: 7.5

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P

CVSS Score Source: CVE-2018-7842


Risk Factor: Critical

Base Score: 9.8

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

Vulnerability Information

CPE: cpe:/o:schneider-electric:modicon_m580_firmware, cpe:/o:schneider-electric:modicon_m340_firmware, cpe:/o:schneider-electric:modicon_quantum_firmware, cpe:/o:schneider-electric:modicon_premium_firmware

Required KB Items: Tenable.ot/Schneider

Exploit Ease: No known exploits are available

Patch Publication Date: 5/22/2019

Vulnerability Publication Date: 5/22/2019

Reference Information

CVE: CVE-2018-7842

CWE: 290