CVE intelligence and bounded remediation

CVE-2020-7477 — Schneider-Electric 140Noe77101 Firmware security vulnerability

High CVSS 7.5

A CWE-754: Improper Check for Unusual or Exceptional Conditions vulnerability exists in Quantum Ethernet Network module 140NOE771x1 (Versions 7.0 and prior), Quantum processors with integrated Ethernet – 140CPU65xxxxx (all Versions), and Premium processors with integrated Ethernet (all Versions), which could cause a Denial of Service when sending a specially crafted command over Modbus.

Severity
High
CVSS
7.5 (3.1)
Published
2020-03-23
CISA KEV
Not currently listed
Ecosystem
operating-system
Weaknesses
CWE-754

Affected products

  • schneider-electric / 140noe77101_firmware
  • schneider-electric / 140noe77111_firmware
  • schneider-electric / tsxh5744m_firmware
  • schneider-electric / tsxh5724m_firmware
  • schneider-electric / tsxp576634m_firmware
  • schneider-electric / tsxp57554m_firmware

Showing 6 representative product identities from 29 source matches. Confirm exact affected versions with the linked vendor and NVD evidence.

Matched remediation archetype

Resource exhaustion and denial of service

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

Check exposure

  • Identify attacker-influenced work factors including input size, nesting, compression, fan-out, regex cost, allocation, recursion, retries, and connection lifetime.
  • Map per-request and shared CPU, memory, disk, descriptor, thread, queue, and downstream-service limits.
  • Determine whether authentication, tenancy, quotas, and rate controls apply before expensive processing begins.

Remediate safely

  • Bound input size, nesting, expansion, work, concurrency, queue depth, retries, and execution time before resource-intensive processing.
  • Release resources on every success, error, cancellation, and timeout path and use backpressure instead of unbounded buffering.
  • Update affected components and add small deterministic tests that assert resource ceilings rather than exhausting a host.

Authoritative sources

Complete CVE record and remediation plan

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