| Internet-Draft | Key Exchange Without Forward Secrecy is | November 2020 |
| Preuß Mattsson | Expires 22 May 2021 | [Page] |
Key exchange without forward secrecy enables passive monitoring [RFC7258]. Massive pervasive monitoring attacks relying on key exchange without forward secrecy has been reported [I-D.ietf-emu-aka-pfs]. If key exchange without Diffe-Hellan is used, compromise of the long-term authenticatation key enables a passive attacker to compromise past and future sessions. All TLS 1.2 cipher suites without forward secrecy has been marked as NOT RECOMMENDED [RFC8447], and static RSA has been forbidden in TLS 1.3 [RFC8446]. psk_ke does not provide forward secrecy and is NOT RECOMMENDED. This document sets the IANA registration of psk_ke to NOT RECOMMENDED.¶
This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79.¶
Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet-Drafts is at https://datatracker.ietf.org/drafts/current/.¶
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This Internet-Draft will expire on 22 May 2021.¶
Copyright (c) 2020 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 (https://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.¶
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here.¶
IANA is requested to update the PskKeyExchangeMode registry under the Transport Layer Security (TLS) Parameters heading. For psk_ke the "Recommended" value has been set to "N".¶
The authors want to thank Ari Keraenen for their valuable comments and feedback.¶