Network Working Group N. Aviram
Internet-Draft 9 July 2021
Intended status: Standards Track
Expires: 10 January 2022
Deprecating Obsolete Key Exchange Methods in TLS
draft-aviram-tls-deprecate-obsolete-kex-00
Abstract
This document deprecates the use of RSA key exchange in TLS, and
limits the use of Diffie Hellman key exchange over a finite field
such as to avoid known vulnerabilities or improper security
properties.
Status of This Memo
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
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This Internet-Draft will expire on 10 January 2022.
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Table of Contents
1. Introduction
1.1. Requirements
2. RSA
3. Ephemeral Finite Field Diffie Hellman
4. IANA Considerations
5. Security Considerations
6. Acknowledgments
7. References
7.1. Normative References
7.2. Informative References
Author's Address
1. Introduction
TLS supports a variety of key exchange algorithms, including RSA and
Diffie Hellman over a finite field, as well as elliptic curve Diffie
Hellman (ECDH). Diffie Hellman key exchange, over any group, may use
either long-lived or ephemeral secrets. Diffie Hellman key exchange
with long-lived secrets over a finite field is already deprecated in
[deprecate-ffdh]. This document focuses on Diffie Hellman over a
finite field with ephemeral secrets (FFDHE), as well as RSA key
exchange.
Recent years have brought to light several security concerns
regarding FFDHE key exchange that stem from implementation choices.
Additionally, RSA key exchange suffers from security problems that
are independent of implementation choices, as well as problems that
stem purely from the difficulty of implementing security
countermeasures correctly.
At a rough glance, the problems affecting FFDHE are as follows:
1. FFDHE suffers from interoperability problems, because there is no
mechanism for negotiating the group size, and some
implementations only support small group sizes; see [RFC7919],
Section 1.
2. In practice, some operators use 1024 bit FFDHE groups, since this
is the maximum size that ensures wide support; see [RFC7919],
Section 1. This size leaves only a small security margin vs. the
current discrete log record, which stands at 795 bits [DLOG795].
3. Expanding on the previous point, a handful of very large
computations would allow cheaply decrypting a relatively large
fraction of FFDHE traffic [weak-dh].
4. When secrets are not fully ephemeral, FFDHE suffers from the
[Raccoon] side channel attack.
5. FFDHE groups may have small subgroups, which may enable several
attacks [subgroups].
And the problems affecting RSA key exchange are as follows:
1. RSA key exchange offers no forward secrecy, by construction.
2. RSA key exchange may be vulnerable to Bleichenbacher's attack
[BLEI]. Experience shows that variants of this attack arise
every few years, because implementing the relevant countermeasure
correctly is difficult; see [ROBOT], [NEW-BLEI], [DROWN].
3. In addition to the above point, there is no convenient mechanism
in TLS for domain separation of keys. Therefore, a single
endpoint that is vulnerable to Bleichenbacher's attack would
affect all endpoints sharing the same RSA key; see [XPROT],
[DROWN].
Given these problems, this document updates [RFC4346], [RFC5246],
[RFC4162], [RFC6347], [RFC5932], [RFC5288], [RFC6209], [RFC6367],
[RFC8422], [RFC5289], and [RFC5469] to deprecate RSA key exchange in
TLS, and limit use of FFDHE such that it provides acceptable security
properties.
1.1. Requirements
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.
2. RSA
Clients and servers MUST NOT offer RSA cipher suites in TLS 1.0, 1.1,
and 1.2 connections. This includes all cipher suites listed in the
following table. Note that these cipher suites are already marked as
not recommended in the "TLS Cipher Suites" registry.
+-----------------------------------------+----------------------------------------------+
| Ciphersuite | Reference |
+=========================================+==============================================+
| TLS_RSA_WITH_NULL_MD5 | [RFC5246] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_WITH_NULL_SHA | [RFC5246] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_EXPORT_WITH_RC4_40_MD5 | [RFC4346][RFC6347] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_WITH_RC4_128_MD5 | [RFC5246][RFC6347] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_WITH_RC4_128_SHA | [RFC5246][RFC6347] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_EXPORT_WITH_RC2_CBC_40_MD5 | [RFC4346] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_WITH_IDEA_CBC_SHA |[RFC5469][SC-tls-des-idea-ciphers-to-historic]|
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_EXPORT_WITH_DES40_CBC_SHA | [RFC4346] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_WITH_DES_CBC_SHA |[RFC5469][SC-tls-des-idea-ciphers-to-historic]|
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_WITH_3DES_EDE_CBC_SHA | [RFC5246] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_PSK_WITH_NULL_SHA | [RFC4785] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_WITH_AES_128_CBC_SHA | [RFC5246] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_WITH_AES_256_CBC_SHA | [RFC5246] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_WITH_NULL_SHA256 | [RFC5246] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_WITH_AES_128_CBC_SHA256 | [RFC5246] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_WITH_AES_256_CBC_SHA256 | [RFC5246] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_WITH_CAMELLIA_128_CBC_SHA | [RFC5932] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_WITH_CAMELLIA_256_CBC_SHA | [RFC5932] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_PSK_WITH_RC4_128_SHA | [RFC4279][RFC6347] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_PSK_WITH_3DES_EDE_CBC_SHA | [RFC4279] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_PSK_WITH_AES_128_CBC_SHA | [RFC4279] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_PSK_WITH_AES_256_CBC_SHA | [RFC4279] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_WITH_SEED_CBC_SHA | [RFC4162] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_WITH_AES_128_GCM_SHA256 | [RFC5288] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_WITH_AES_256_GCM_SHA384 | [RFC5288] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_PSK_WITH_AES_128_GCM_SHA256 | [RFC5487] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_PSK_WITH_AES_256_GCM_SHA384 | [RFC5487] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_PSK_WITH_AES_128_CBC_SHA256 | [RFC5487] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_PSK_WITH_AES_256_CBC_SHA384 | [RFC5487] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_PSK_WITH_NULL_SHA256 | [RFC5487] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_PSK_WITH_NULL_SHA384 | [RFC5487] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_WITH_CAMELLIA_128_CBC_SHA256 | [RFC5932] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_WITH_CAMELLIA_256_CBC_SHA256 | [RFC5932] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_WITH_ARIA_128_CBC_SHA256 | [RFC6209] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_WITH_ARIA_256_CBC_SHA384 | [RFC6209] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_WITH_ARIA_128_GCM_SHA256 | [RFC6209] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_WITH_ARIA_256_GCM_SHA384 | [RFC6209] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_PSK_WITH_ARIA_128_CBC_SHA256 | [RFC6209] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_PSK_WITH_ARIA_256_CBC_SHA384 | [RFC6209] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_PSK_WITH_ARIA_128_GCM_SHA256 | [RFC6209] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_PSK_WITH_ARIA_256_GCM_SHA384 | [RFC6209] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_WITH_CAMELLIA_128_GCM_SHA256 | [RFC6367] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_WITH_CAMELLIA_256_GCM_SHA384 | [RFC6367] |
+-----------------------------------------+----------------------------------------------+
|TLS_RSA_PSK_WITH_CAMELLIA_128_GCM_SHA256 | [RFC6367] |
+-----------------------------------------+----------------------------------------------+
|TLS_RSA_PSK_WITH_CAMELLIA_256_GCM_SHA384 | [RFC6367] |
+-----------------------------------------+----------------------------------------------+
|TLS_RSA_PSK_WITH_CAMELLIA_128_CBC_SHA256 | [RFC6367] |
+-----------------------------------------+----------------------------------------------+
|TLS_RSA_PSK_WITH_CAMELLIA_256_CBC_SHA384 | [RFC6367] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_WITH_AES_128_CCM | [RFC6655] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_WITH_AES_256_CCM | [RFC6655] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_WITH_AES_128_CCM_8 | [RFC6655] |
+-----------------------------------------+----------------------------------------------+
| TLS_RSA_WITH_AES_256_CCM_8 | [RFC6655] |
+-----------------------------------------+----------------------------------------------+
|TLS_RSA_PSK_WITH_CHACHA20_POLY1305_SHA256| [RFC7905] |
+-----------------------------------------+----------------------------------------------+
Table 1
3. Ephemeral Finite Field Diffie Hellman
Clients and servers MAY offer fully ephemeral FFDHE cipher suites in
TLS 1.0, 1.1, and 1.2 connections, under the following conditions:
1. The secret DH key is fully ephemeral, that is, a fresh DH
exponent is generated for each TLS connection. Note that this
requirement is also specified in [deprecate-ffdh].
2. The group is one of the following well-known groups described in
[RFC7919]: ffdhe2048, ffdhe3072, ffdhe4096, ffdhe6144, ffdhe8192.
We note that previously, supporting the broadest range of clients
would have required supporting either RSA key exchange, or 1024-bit
FFDHE. This is no longer the case, and it is possible to support
most clients released since circa 2015 using 2048-bit FFDHE, or more
modern key exchange methods, and without RSA key exchange
[server_side_tls].
The above requirements apply to all cipher suites listed in the
following table.
+-----------------------------------------+----------------------------------------------+
| Ciphersuite | Reference |
+=========================================+==============================================+
| TLS_DHE_DSS_EXPORT_WITH_DES40_CBC_SHA | [RFC4346] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_DSS_WITH_DES_CBC_SHA |[RFC5469][SC-tls-des-idea-ciphers-to-historic]|
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_DSS_WITH_3DES_EDE_CBC_SHA | [RFC5246] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_RSA_EXPORT_WITH_DES40_CBC_SHA | [RFC4346] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_RSA_WITH_DES_CBC_SHA |[RFC5469][SC-tls-des-idea-ciphers-to-historic]|
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_RSA_WITH_3DES_EDE_CBC_SHA | [RFC5246] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_PSK_WITH_NULL_SHA | [RFC4785] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_DSS_WITH_AES_128_CBC_SHA | [RFC5246] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_RSA_WITH_AES_128_CBC_SHA | [RFC5246] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_DSS_WITH_AES_256_CBC_SHA | [RFC5246] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_RSA_WITH_AES_256_CBC_SHA | [RFC5246] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_DSS_WITH_AES_128_CBC_SHA256 | [RFC5246] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_DSS_WITH_CAMELLIA_128_CBC_SHA | [RFC5932] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_RSA_WITH_CAMELLIA_128_CBC_SHA | [RFC5932] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_RSA_WITH_AES_128_CBC_SHA256 | [RFC5246] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_DSS_WITH_AES_256_CBC_SHA256 | [RFC5246] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_RSA_WITH_AES_256_CBC_SHA256 | [RFC5246] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_DSS_WITH_CAMELLIA_256_CBC_SHA | [RFC5932] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_RSA_WITH_CAMELLIA_256_CBC_SHA | [RFC5932] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_PSK_WITH_RC4_128_SHA | [RFC4279][RFC6347] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_PSK_WITH_3DES_EDE_CBC_SHA | [RFC4279] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_PSK_WITH_AES_128_CBC_SHA | [RFC4279] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_PSK_WITH_AES_256_CBC_SHA | [RFC4279] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_DSS_WITH_SEED_CBC_SHA | [RFC4162] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_RSA_WITH_SEED_CBC_SHA | [RFC4162] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_RSA_WITH_AES_128_GCM_SHA256 | [RFC5288] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_RSA_WITH_AES_256_GCM_SHA384 | [RFC5288] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_DSS_WITH_AES_128_GCM_SHA256 | [RFC5288] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_DSS_WITH_AES_256_GCM_SHA384 | [RFC5288] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_PSK_WITH_AES_128_GCM_SHA256 | [RFC5487] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_PSK_WITH_AES_256_GCM_SHA384 | [RFC5487] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_PSK_WITH_AES_128_CBC_SHA256 | [RFC5487] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_PSK_WITH_AES_256_CBC_SHA384 | [RFC5487] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_PSK_WITH_NULL_SHA256 | [RFC5487] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_PSK_WITH_NULL_SHA384 | [RFC5487] |
+-----------------------------------------+----------------------------------------------+
|TLS_DHE_DSS_WITH_CAMELLIA_128_CBC_SHA256 | [RFC5932] |
+-----------------------------------------+----------------------------------------------+
|TLS_DHE_RSA_WITH_CAMELLIA_128_CBC_SHA256 | [RFC5932] |
+-----------------------------------------+----------------------------------------------+
|TLS_DHE_DSS_WITH_CAMELLIA_256_CBC_SHA256 | [RFC5932] |
+-----------------------------------------+----------------------------------------------+
|TLS_DHE_RSA_WITH_CAMELLIA_256_CBC_SHA256 | [RFC5932] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_DSS_WITH_ARIA_128_CBC_SHA256 | [RFC6209] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_DSS_WITH_ARIA_256_CBC_SHA384 | [RFC6209] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_RSA_WITH_ARIA_128_CBC_SHA256 | [RFC6209] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_RSA_WITH_ARIA_256_CBC_SHA384 | [RFC6209] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_RSA_WITH_ARIA_128_GCM_SHA256 | [RFC6209] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_RSA_WITH_ARIA_256_GCM_SHA384 | [RFC6209] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_DSS_WITH_ARIA_128_GCM_SHA256 | [RFC6209] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_DSS_WITH_ARIA_256_GCM_SHA384 | [RFC6209] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_PSK_WITH_ARIA_128_CBC_SHA256 | [RFC6209] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_PSK_WITH_ARIA_256_CBC_SHA384 | [RFC6209] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_PSK_WITH_ARIA_128_GCM_SHA256 | [RFC6209] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_PSK_WITH_ARIA_256_GCM_SHA384 | [RFC6209] |
+-----------------------------------------+----------------------------------------------+
|TLS_DHE_RSA_WITH_CAMELLIA_128_GCM_SHA256 | [RFC6367] |
+-----------------------------------------+----------------------------------------------+
|TLS_DHE_RSA_WITH_CAMELLIA_256_GCM_SHA384 | [RFC6367] |
+-----------------------------------------+----------------------------------------------+
|TLS_DHE_DSS_WITH_CAMELLIA_128_GCM_SHA256 | [RFC6367] |
+-----------------------------------------+----------------------------------------------+
|TLS_DHE_DSS_WITH_CAMELLIA_256_GCM_SHA384 | [RFC6367] |
+-----------------------------------------+----------------------------------------------+
|TLS_DHE_PSK_WITH_CAMELLIA_128_GCM_SHA256 | [RFC6367] |
+-----------------------------------------+----------------------------------------------+
|TLS_DHE_PSK_WITH_CAMELLIA_256_GCM_SHA384 | [RFC6367] |
+-----------------------------------------+----------------------------------------------+
|TLS_DHE_PSK_WITH_CAMELLIA_128_CBC_SHA256 | [RFC6367] |
+-----------------------------------------+----------------------------------------------+
|TLS_DHE_PSK_WITH_CAMELLIA_256_CBC_SHA384 | [RFC6367] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_RSA_WITH_AES_128_CCM | [RFC6655] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_RSA_WITH_AES_256_CCM | [RFC6655] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_RSA_WITH_AES_128_CCM_8 | [RFC6655] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_RSA_WITH_AES_256_CCM_8 | [RFC6655] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_PSK_WITH_AES_128_CCM | [RFC6655] |
+-----------------------------------------+----------------------------------------------+
| TLS_DHE_PSK_WITH_AES_256_CCM | [RFC6655] |
+-----------------------------------------+----------------------------------------------+
|TLS_DHE_RSA_WITH_CHACHA20_POLY1305_SHA256| [RFC7905] |
+-----------------------------------------+----------------------------------------------+
|TLS_DHE_PSK_WITH_CHACHA20_POLY1305_SHA256| [RFC7905] |
+-----------------------------------------+----------------------------------------------+
Table 2
Note that FFDH cipher suites are already deprecated in
[deprecate-ffdh].
4. IANA Considerations
This document makes no requests to IANA. Note that all cipher suites
listed in Section 2 are already marked as not recommended in the "TLS
Cipher Suites" registry.
5. Security Considerations
This document is entirely about security.
6. Acknowledgments
This document was inspired by discussion on the TLS WG mailing list
and a suggestion by Filippo Valsorda following the release of the
[Raccoon] attack. Thanks to Christopher A. Wood and Carrick D.
Bartle for useful feedback, discussions, and ideas.
7. References
7.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC4162] Lee, H.J., Yoon, J.H., and J.I. Lee, "Addition of SEED
Cipher Suites to Transport Layer Security (TLS)",
RFC 4162, DOI 10.17487/RFC4162, August 2005,
<https://www.rfc-editor.org/info/rfc4162>.
[RFC4279] Eronen, P., Ed. and H. Tschofenig, Ed., "Pre-Shared Key
Ciphersuites for Transport Layer Security (TLS)",
RFC 4279, DOI 10.17487/RFC4279, December 2005,
<https://www.rfc-editor.org/info/rfc4279>.
[RFC4346] Dierks, T. and E. Rescorla, "The Transport Layer Security
(TLS) Protocol Version 1.1", RFC 4346,
DOI 10.17487/RFC4346, April 2006,
<https://www.rfc-editor.org/info/rfc4346>.
[RFC4785] Blumenthal, U. and P. Goel, "Pre-Shared Key (PSK)
Ciphersuites with NULL Encryption for Transport Layer
Security (TLS)", RFC 4785, DOI 10.17487/RFC4785, January
2007, <https://www.rfc-editor.org/info/rfc4785>.
[RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security
(TLS) Protocol Version 1.2", RFC 5246,
DOI 10.17487/RFC5246, August 2008,
<https://www.rfc-editor.org/info/rfc5246>.
[RFC5288] Salowey, J., Choudhury, A., and D. McGrew, "AES Galois
Counter Mode (GCM) Cipher Suites for TLS", RFC 5288,
DOI 10.17487/RFC5288, August 2008,
<https://www.rfc-editor.org/info/rfc5288>.
[RFC5289] Rescorla, E., "TLS Elliptic Curve Cipher Suites with SHA-
256/384 and AES Galois Counter Mode (GCM)", RFC 5289,
DOI 10.17487/RFC5289, August 2008,
<https://www.rfc-editor.org/info/rfc5289>.
[RFC5469] Eronen, P., Ed., "DES and IDEA Cipher Suites for Transport
Layer Security (TLS)", RFC 5469, DOI 10.17487/RFC5469,
February 2009, <https://www.rfc-editor.org/info/rfc5469>.
[RFC5487] Badra, M., "Pre-Shared Key Cipher Suites for TLS with SHA-
256/384 and AES Galois Counter Mode", RFC 5487,
DOI 10.17487/RFC5487, March 2009,
<https://www.rfc-editor.org/info/rfc5487>.
[RFC5932] Kato, A., Kanda, M., and S. Kanno, "Camellia Cipher Suites
for TLS", RFC 5932, DOI 10.17487/RFC5932, June 2010,
<https://www.rfc-editor.org/info/rfc5932>.
[RFC6209] Kim, W., Lee, J., Park, J., and D. Kwon, "Addition of the
ARIA Cipher Suites to Transport Layer Security (TLS)",
RFC 6209, DOI 10.17487/RFC6209, April 2011,
<https://www.rfc-editor.org/info/rfc6209>.
[RFC6347] Rescorla, E. and N. Modadugu, "Datagram Transport Layer
Security Version 1.2", RFC 6347, DOI 10.17487/RFC6347,
January 2012, <https://www.rfc-editor.org/info/rfc6347>.
[RFC6367] Kanno, S. and M. Kanda, "Addition of the Camellia Cipher
Suites to Transport Layer Security (TLS)", RFC 6367,
DOI 10.17487/RFC6367, September 2011,
<https://www.rfc-editor.org/info/rfc6367>.
[RFC6655] McGrew, D. and D. Bailey, "AES-CCM Cipher Suites for
Transport Layer Security (TLS)", RFC 6655,
DOI 10.17487/RFC6655, July 2012,
<https://www.rfc-editor.org/info/rfc6655>.
[RFC7905] Langley, A., Chang, W., Mavrogiannopoulos, N.,
Strombergson, J., and S. Josefsson, "ChaCha20-Poly1305
Cipher Suites for Transport Layer Security (TLS)",
RFC 7905, DOI 10.17487/RFC7905, June 2016,
<https://www.rfc-editor.org/info/rfc7905>.
[RFC7919] Gillmor, D., "Negotiated Finite Field Diffie-Hellman
Ephemeral Parameters for Transport Layer Security (TLS)",
RFC 7919, DOI 10.17487/RFC7919, August 2016,
<https://www.rfc-editor.org/info/rfc7919>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC8422] Nir, Y., Josefsson, S., and M. Pegourie-Gonnard, "Elliptic
Curve Cryptography (ECC) Cipher Suites for Transport Layer
Security (TLS) Versions 1.2 and Earlier", RFC 8422,
DOI 10.17487/RFC8422, August 2018,
<https://www.rfc-editor.org/info/rfc8422>.
7.2. Informative References
[BLEI] Bleichenbacher, D., "Chosen Ciphertext Attacks against
Protocols Based on RSA Encryption Standard PKCS #1",
Advances in Cryptology -- CRYPTO'98, LNCS vol. 1462,
pages: 1-12 , 1998.
[deprecate-ffdh]
Bartle, C., Aviram, N., and F. Valsorda, "Deprecating FFDH
Ciphersuites in TLS", June 2021,
<https://datatracker.ietf.org/doc/draft-bartle-tls-
deprecate-ffdhe/>.
[DLOG795] Boudot, F., Gaudry, P., Guillevic, A., Heninger, N.,
Thomé, E., and P. Zimmermann, "Comparing the difficulty of
factorization and discrete logarithm: a 240-digit
experiment", 17 August 2020,
<https://eprint.iacr.org/2020/697>.
[DROWN] Aviram, N., Schinzel, S., Somorovsky, J., Heninger, N.,
Dankel, M., Steube, J., Valenta, L., Adrian, D.,
Halderman, J.A., Dukhovni, V., Käsper, E., Cohney, S.,
Engels, S., Paar, C., and Y. Shavitt, "DROWN: Breaking TLS
using SSLv2", August 2016,
<https://drownattack.com/drown-attack-paper.pdf>.
[NEW-BLEI] Meyer, C., Somorovsky, J., Weiss, E., Schwenk, J.,
Schinzel, S., and E. Tews, "Revisiting SSL/TLS
Implementations: New Bleichenbacher Side Channels and
Attacks", August 2014,
<https://www.usenix.org/system/files/conference/
usenixsecurity14/sec14-paper-meyer.pdf>.
[Raccoon] Merget, R., Brinkmann, M., Aviram, N., Somorovsky, J.,
Mittmann, J., and J. Schwenk, "Raccoon Attack: Finding and
Exploiting Most-Significant-Bit-Oracles in TLS-DH(E)", 9
September 2020,
<https://raccoon-attack.com/RacoonAttack.pdf>.
[ROBOT] Boeck, H., Somorovsky, J., and C. Young, "Return Of
Bleichenbacher's Oracle Threat (ROBOT)", 27th USENIX
Security Symposium , 2018.
[SC-tls-des-idea-ciphers-to-historic]
"Moving single-DES and IDEA TLS ciphersuites to Historic",
25 January 2021, <https://datatracker.ietf.org/doc/status-
change-tls-des-idea-ciphers-to-historic/>.
[server_side_tls]
King, A., "Server Side TLS", July 2020,
<https://wiki.mozilla.org/Security/Server_Side_TLS>.
[subgroups]
Valenta, L., Adrian, D., Sanso, A., Cohney, S., Fried, J.,
Hastings, M., Halderman, J.A., and N. Heninger, "Measuring
small subgroup attacks against Diffie-Hellman", 15 October
2016, <https://eprint.iacr.org/2016/995/20161017:193515>.
[weak-dh] Adrian, D., Bhargavan, K., Durumeric, Z., Gaudry, P.,
Green, M., Halderman, J.A., Heninger, N., Springall, D.,
Thomé, E., Valenta, L., VanderSloot, B., Wustrow, E.,
Zanella-Béguelin, S., and P. Zimmermann, "Weak Diffie-
Hellman and the Logjam Attack", October 2015,
<https://weakdh.org/>.
[XPROT] Jager, T., Schwenk, J., and J. Somorovsky, "On the
Security of TLS 1.3 and QUIC Against Weaknesses in PKCS#1
v1.5 Encryption", Proceedings of the 22nd ACM SIGSAC
Conference on Computer and Communications Security , 2015.
Author's Address
Nimrod Aviram
Email: nimrod.aviram@gmail.com