CVE-2005-4441: The PVLAN protocol allows remote attackers to bypass network segmentation and spoof PVLAN traffic via a PVL...

Security readout for executives and security teams

This CVE describes a way PVLAN network isolation can be bypassed so traffic reaches systems that were meant to be separated. The record does not identify a specific vendor, product, CVSS score, patch, or known active exploitation. Treat this as a design and configuration exposure for networks relying on PVLAN segmentation. Exposure is most likely in networks using PVLAN or unidirectional VLAN isolation as a security boundary. The CVE data lists affected vendor and product as n/a, so exposure must be assessed against actual switch, router, and segmentation designs. Prioritize review if PVLANs protect sensitive environments, multi-tenant networks, or regulated workloads. Otherwise, handle as a segmentation assurance item because severity, affected products, and fixes are not defined in the supplied sources. Mitigation focus: Check switch and router vendor advisories for PVLAN isolation guidance and fixes.; Review PVLAN designs that rely on gateway-mediated isolation between hosts.; Avoid relying solely on PVLAN isolation for high-trust security boundaries..

Prepared

Jun 29, 2026, 15:49 UTC (UTC+00:00)

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