CVE-2018-13991: The WebUI of PHOENIX CONTACT FL SWITCH 3xxx, 4xxx, 48xx versions 1.0 to 1.34 leaks private information in f...

Security readout for executives and security teams

Some PHOENIX CONTACT industrial switches can disclose private information through their WebUI when running firmware versions 1.0 through 1.34. The issue is remotely reachable and does not require authentication, but the published impact is limited to confidentiality. Treat it as an exposure-reduction priority for operational technology networks. Exposure is most likely where affected PHOENIX CONTACT FL SWITCH WebUIs are reachable on corporate, remote-access, or internet-facing networks. OT environments with unmanaged switch inventories or broadly accessible management interfaces have higher practical risk. Prioritize remediation where affected switches manage production, safety-adjacent, or remote OT network segments. The known impact is information disclosure, not direct disruption, but exposed management interfaces can increase follow-on risk. Mitigation focus: Identify affected FL SWITCH 3xxx, 4xxx, and 48xx devices.; Check firmware versions for 1.0 through 1.34.; Restrict WebUI access to trusted management networks only..

Prepared

Jun 1, 2026, 04:16 UTC (UTC+00:00)

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.