CVE intelligence and bounded remediation

CVE-2018-7833 — Schneider-Electric Modicom M340 Firmware security vulnerability

High CVSS 7.5

An Improper Check for Unusual or Exceptional Conditions vulnerability exists in the embedded web servers in all Modicon M340, Premium, Quantum PLCs and BMXNOR0200 where an unauthenticated user can send a specially crafted XML data via a POST request to cause the web server to become unavailable

Severity
High
CVSS
7.5 (3.0)
Published
2018-12-17
CISA KEV
Not currently listed
Ecosystem
operating-system
Weaknesses
CWE-754

Affected products

  • schneider-electric / modicom_m340_firmware
  • schneider-electric / modicom_premium_firmware
  • schneider-electric / modicom_quantum_firmware
  • schneider-electric / modicom_bmxnor0200h_firmware

Matched remediation archetype

General vulnerability remediation

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Confirm the affected component, deployment paths, reachable interfaces, and enabled features from inventories and configuration, without probing production destructively.
  • Compare the advisory's affected conditions with the repository lockfiles, build manifests, artifacts, and runtime inventory.
  • Identify data sensitivity, trust boundaries, and privilege level for every confirmed affected deployment.

Remediate safely

  • Apply a vendor-supported fix or remove the affected component or feature; record the selected change and its source in the repository.
  • Update direct and transitive dependency locks, generated artifacts, deployment manifests, and asset inventories together.
  • Add a regression test for the documented unsafe condition using inert inputs and preserve rollback instructions.

Authoritative sources

Complete CVE record and remediation plan

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