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Virtual Private Network (VPN) traffic leakages in dual-stack hosts/ networks

The information below is for an old version of the document.
Document Type
This is an older version of an Internet-Draft that was ultimately published as RFC 7359.
Expired & archived
Author Fernando Gont
Last updated 2013-06-15 (Latest revision 2012-12-12)
Replaces draft-gont-opsec-vpn-leakages
RFC stream Internet Engineering Task Force (IETF)
Additional resources Mailing list discussion
Stream WG state WG Document
Document shepherd (None)
IESG IESG state Expired
Consensus boilerplate Unknown
Telechat date (None)
Responsible AD (None)
Send notices to (None)

This Internet-Draft is no longer active. A copy of the expired Internet-Draft is available in these formats:


The subtle way in which the IPv6 and IPv4 protocols co-exist in typical networks, together with the lack of proper IPv6 support in popular Virtual Private Network (VPN) products, may inadvertently result in VPN traffic leaks. That is, traffic meant to be transferred over a VPN connection may leak out of such connection and be transferred in the clear on the local network. This document discusses some scenarios in which such VPN leakages may occur, either as a side effect of enabling IPv6 on a local network, or as a result of a deliberate attack from a local attacker. Additionally, it discusses possible mitigations for the aforementioned issue.


Fernando Gont

(Note: The e-mail addresses provided for the authors of this Internet-Draft may no longer be valid.)