CVE intelligence and bounded remediation

CVE-2023-23451 — The Flexi Classic and Flexi Soft Gateways SICK UE410-EN3 FLEXI ETHERNET GATEW

Critical CVSS 9.8

The Flexi Classic and Flexi Soft Gateways SICK UE410-EN3 FLEXI ETHERNET GATEW. with serial number <=2311xxxx all Firmware versions, SICK UE410-EN1 FLEXI ETHERNET GATEW. with serial number <=2311xxxx all Firmware versions, SICK UE410-EN3S04 FLEXI ETHERNET GATEW. with serial number <=2311xxxx all Firmware versions, SICK UE410-EN4 FLEXI ETHERNET GATEW. with serial number <=2311xxxx all Firmware versions, SICK FX0-GENT00000 FLEXISOFT EIP GATEW. with serial number <=2311xxxx with Firmware <=V2.11.0, SICK FX0-GMOD00000 FLEXISOFT MOD GATEW. with serial number <=2311xxxx with Firmware <=V2.11.0, SICK FX0-GPNT00000 FLEXISOFT PNET GATEW. with serial number <=2311xxxx with Firmware <=V2.12.0, SICK FX0-GENT00030 FLEXISOFT EIP GATEW.V2 with serial number <=2311xxxx all Firmware versions, SICK FX0-GPNT00030 FLEXISOFT PNET GATEW.V2 with serial number <=2311xxxx all Firmware versions and SICK FX0-GMOD00010 FLEXISOFT MOD GW with serial number <=2311xxxx with Firmware <=V2.11.0 all have Telnet enabled by factory default. No password is set in the default configuration.

Severity
Critical
CVSS
9.8 (3.1)
Published
2023-04-19
CISA KEV
Not currently listed
Ecosystem
operating-system
Weaknesses
CWE-477, CWE-306

Affected products

  • sick / ue410-en3_firmware
  • sick / ue410-en1_firmware
  • sick / ue410-en3s04_firmware
  • sick / ue410-en4_firmware
  • sick / fx0-gent00000_firmware
  • sick / fx0-gmod00000_firmware

Showing 6 representative product identities from 10 source matches. Confirm exact affected versions with the linked vendor and NVD evidence.

Matched remediation archetype

Authentication bypass and missing authentication

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

Check exposure

  • Map every affected endpoint and protocol path, including alternate ports, legacy routes, recovery flows, service accounts, and machine-to-machine access.
  • Confirm which deployments enable the affected authentication mode and whether the interface is reachable from untrusted networks.
  • Review session, token, credential, and proxy trust configuration without attempting account takeover.

Remediate safely

  • Apply the supported fix and centralize fail-closed authentication before protected request handling.
  • Remove default or embedded credentials, rotate affected secrets and sessions, and bind authentication decisions to the intended audience and channel.
  • Add negative tests for alternate routes, malformed or absent credentials, recovery flows, and proxy-derived identity.

Authoritative sources

Complete CVE record and remediation plan

The detailed catalog view below loads this exact record, its source evidence, and the full seven-phase agentic change plan.