CVE intelligence and bounded remediation

CVE-2020-12523 — Phoenixcontact Tc Mguard Rs4000 4G Vzw Vpn Firmware security vulnerability

Critical CVSS 9.1

On Phoenix Contact mGuard Devices versions before 8.8.3 LAN ports get functional after reboot even if they are disabled in the device configuration. For mGuard devices with integrated switch on the LAN side, single switch ports can be disabled by device configuration. After a reboot these ports get functional independent from their configuration setting: Missing Initialization of Resource

Severity
Critical
CVSS
9.1 (3.1)
Published
2020-12-17
CISA KEV
Not currently listed
Ecosystem
operating-system
Weaknesses
CWE-909

Affected products

  • phoenixcontact / tc_mguard_rs4000_4g_vzw_vpn_firmware
  • phoenixcontact / tc_mguard_rs4000_4g_att_vpn_firmware
  • phoenixcontact / fl_mguard_rs4004_tx/dtx_firmware
  • phoenixcontact / fl_mguard_rs4004_tx/dtx_vpn_firmware
  • phoenixcontact / tc_mguard_rs4000_3g_vpn_firmware
  • phoenixcontact / tc_mguard_rs4000_4g_vpn_firmware

Showing 6 representative product identities from 9 source matches. Confirm exact affected versions with the linked vendor and NVD evidence.

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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