Configuration errors on Provider Edge (PE) routers in Layer-3 VPN networks based on [RFC2547] can lead to security breaches of the connected VPNs. For example, the PE router could be mistakenly configured such that a connected Customer Edge (CE) router belongs to an incorrect VPN. Here we propose a scheme that verifies local and remote routing information received by the PE router before it installs new VPN routes into the Virtual Routing & Forwarding Instance (VRF). The proposed changes affect only the PE routers.