CriticalCVE-2018-7842

Modicon M580 Modicon M340 Modicon Quantum Modicon Premium: Authentication Bypass (CVE-2018-7842)

Published 22.05.2019Sources: CVE.org, Schneider Electric

Public exploit

What is affected, what to do

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.

An exploit is publicly available. The available sources name no fixed version. Check the vendor guidance in the references below.

Affected: Modicon M580 Modicon M340 Modicon Quantum Modicon Premium eq Modicon M580 Modicon M340 Modicon Quantum Modicon Premium..Modicon M580 Modicon M340 Modicon Quantum Modicon Premium

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Metrics

9.8

Priority

XIEM Effective CVSS: highest available CVSS rating from NVD and vendor data.

Source: NVD, CVSS v3

9.8

CVSS v3

Severity Critical on the scale from 0 to 10.

Source: CVE.org, Schneider Electric

35.0 %

EPSS score

Elevated — model estimates 10-50% exploitation likelihood.

Source: FIRST EPSS, percentile 98.4

Show all metrics

Severity: Critical
Priority (0–325) The priority score is a consolidated metric that condenses several individual signals into a single, action-guiding ranking: technical severity (CVSS), exploitation likelihood (EPSS), known-exploited status (KEV) and the context of the affected asset. The aim is to answer the only truly important question in vulnerability management: what first? Read in glossary: 126.52 Methodology
Exploit maturity An exploit is code or a technique that specifically uses a concrete vulnerability to force unintended behaviour — such as executing code or escalating privileges. It is the tool that turns a theoretical flaw into a practical attack. Read in glossary: PoC (publicly reported)
XIEM Effective CVSS XIEM® is the tiered managed-security operating model from NEOSEC and a registered trademark of NEOSEC GmbH. It extends classic SIEM — the central collection, normalisation and correlation of security-relevant events — with endpoint forensics, network visibility and deception technology, and consolidates them into three building tiers: Sentry, Orchestrate and Command. Read in glossary: 9.8 Methodology
CVSS v3 CVSS is the globally established, open standard for assessing the technical severity of a vulnerability on a scale from 0 to 10. It describes how easily a flaw can be exploited and what damage it can cause — but not how likely its actual exploitation is. CVSS and the complementary EPSS deliberately answer different questions. Read in glossary: 9.8
EPSS score The EPSS score is the absolute model output for an individual vulnerability: the estimated probability of real-world exploitation within the next 30 days, expressed as a value between 0 and 1 (i.e. 0 % to 100 %). A score of 0.42 means „the model estimates a 42 % chance of real-world exploitation within 30 days“. Read in glossary: 35.0 %; Elevated — model estimates 10-50% exploitation likelihood.
EPSS percentile The EPSS percentile is the relative position of a vulnerability within all EPSS-scored CVEs, expressed as a value between 0 and 1. A percentile of 0.90 means „this CVE has a higher EPSS score than 90 % of all other scored CVEs“. Unlike the EPSS score, it is not a probability — but a positioning within a ranking. Read in glossary: 98.4; Critical — this CVE ranks in the top fifth of all CVEs scored today (rank ≥ 80%).
KEV status The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching. Read in glossary: —
Published: 22.05.2019

Detection rules

No NEOSEC detection rule is available for this vulnerability yet.

Classification under NIS2 and CRA

Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.

NIS2 NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management. Read in glossary: High technical severity: assess and remediate the vulnerability in vulnerability handling under Art. 21(2)(e) NIS2 and document the decision.
CRA The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates. Read in glossary: From 11.12.2027, Annex I Part II CRA requires manufacturers of affected products with digital elements to handle vulnerabilities without delay and provide security updates.
ISO/IEC 27001 ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security. Read in glossary: Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.

Description

Source: cvelistv5, schneider_csaf, NVD (NIST)

Affected products

The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.

Affected products
Vendor	Product	Affected versions	Fixed in
—	Modicon M580 Modicon M340 Modicon Quantum Modicon Premium	`Modicon M580 Modicon M340 Modicon Quantum Modicon Premium`	—
Schneider Electric	EcoStruxure Control Expert	`15.1`	—
Schneider Electric	Modicon M340 Firmware	`3.60`	—
Schneider Electric	Modicon M580 Firmware	`4.20`	—
Schneider Electric	Modicon MC80 Firmware	`1.80` `2.20`	— —
Schneider Electric	Modicon Momentum Unity M1E Processor Firmware	`2.90`	—
Schneider Electric	Modicon Premium Firmware	`3.20`	—
Schneider Electric	Modicon Quantum Firmware	`3.60`	—

Vendors and products

Affected operating systems

Affected operating systems
Family	Vendor	Product	Version
Other	schneider-electric	modicon_m340_firmware	—
Other	schneider-electric	modicon_m580_firmware	—
Other	schneider-electric	modicon_premium_firmware	—
Other	schneider-electric	modicon_quantum_firmware	—

Public exploit references

Publicly reported proof-of-concepts, exploit modules and detection templates for this vulnerability. NEOSEC links to the original sources only and does not provide any exploit code.

Public exploit references
Source	Reference	Maturity	Published
Reference tagged as exploit	talosintelligence.com (opens in a new tab)	PoC (publicly reported)reported, not verified	—

References & sources

schneider-electric.comen/download/document/SEVD-2019-134-11x_refsource_MISC, Vendor advisory
talosintelligence.comvulnerability_reports/TALOS-2018-0741x_refsource_MISC, Exploit, Third-party advisory

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