The Network Endpoint Assessment (NEA) Asokan Attack Analysis
RFC 6813
Document | Type |
RFC - Informational
(December 2012; No errata)
Was draft-ietf-nea-asokan (nea WG)
|
|
---|---|---|---|
Authors | Joseph Salowey , Steve Hanna | ||
Last updated | 2015-10-14 | ||
Replaces | draft-salowey-nea-asokan | ||
Stream | IETF | ||
Formats | plain text html pdf htmlized bibtex | ||
Stream | WG state | WG Document | |
Document shepherd | No shepherd assigned | ||
IESG | IESG state | RFC 6813 (Informational) | |
Consensus Boilerplate | Unknown | ||
Telechat date | |||
Responsible AD | Stephen Farrell | ||
IESG note | Susan Thomson (sethomso@cisco.com) is the Document Shepherd. | ||
Send notices to | (None) |
Internet Engineering Task Force (IETF) J. Salowey Request for Comments: 6813 Cisco Systems Category: Informational S. Hanna ISSN: 2070-1721 Juniper Networks December 2012 The Network Endpoint Assessment (NEA) Asokan Attack Analysis Abstract The Network Endpoint Assessment (NEA) protocols are subject to a subtle forwarding attack that has become known as the NEA Asokan Attack. This document describes the attack and countermeasures that may be mounted. Status of This Memo This document is not an Internet Standards Track specification; it is published for informational purposes. This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Not all documents approved by the IESG are a candidate for any level of Internet Standard; see Section 2 of RFC 5741. Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at http://www.rfc-editor.org/info/rfc6813. Copyright Notice Copyright (c) 2012 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Salowey & Hanna Informational [Page 1] RFC 6813 NEA Asokan Attack Analysis December 2012 Table of Contents 1. Introduction ....................................................2 2. NEA Asokan Attack Explained .....................................2 3. Lying Endpoints .................................................4 4. Countermeasures against the NEA Asokan Attack ...................4 4.1. Identity Binding ...........................................4 4.2. Cryptographic Binding ......................................5 4.2.1. Binding Options .....................................5 5. Conclusions .....................................................6 6. Security Considerations .........................................6 7. Informative References ..........................................7 8. Acknowledgments .................................................7 1. Introduction The Network Endpoint Assessment (NEA) [2] protocols are subject to a subtle forwarding attack that has become known as the NEA Asokan Attack. This document describes the attack and countermeasures that may be mounted. The Posture Transport (PT) protocols developed by the NEA working group, PT-TLS [5] and PT-EAP [6], include mechanisms that can provide cryptographic-binding and identity-binding countermeasures. 2. NEA Asokan Attack Explained The NEA Asokan Attack is a variation on an attack described in a 2002 paper written by Asokan, Niemi, and Nyberg [1]. Figure 1 depicts one version of the original Asokan attack. This attack involves tricking an authorized user into authenticating to a decoy Authentication, Authorization, and Accounting (AAA) server, which forwards the authentication protocol from one tunnel to another, tricking the real AAA server into believing these messages originated from the attacker-controlled machine. As a result, the real AAA server grants access to the attacker-controlled machine. Salowey & Hanna Informational [Page 2] RFC 6813 NEA Asokan Attack Analysis December 2012 +-------------+ ========== +----------+ | Attacker |-AuthProto--|AAA Server| +-------------+ ========== +----------+ | AuthProto | +--------------+ ========== +----------------+ |AuthorizedUser|-AuthProto--|Decoy AAA Server| +--------------+ ========== +----------------+ Figure 1: One Example of Original Asokan Attack As described in the NEA Overview [2], the NEA Reference Model is composed of several nested protocols. The Posture Attribute (PA) protocol is nested in the Posture Broker (PB) protocol, which isShow full document text