Insecure Cipher Suite

IANA name:

TLS_ECDH_anon_WITH_AES_128_CBC_SHA

OpenSSL name:

AECDH-AES128-SHA

GnuTLS name:

TLS_ECDH_ANON_AES_128_CBC_SHA1

Hex code:

0xC0, 0x18

TLS Version(s):

TLS1.0, TLS1.1, TLS1.2

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Protocol:

Transport Layer Security (TLS)

Key Exchange:

Elliptic Curve Diffie-Hellman (ECDH)

Non-ephemeral Diffie-Hellman:

Diffie-Hellman key exchanges not using ephemeral keys do not support Perfect Forward Secrecy (PFS) which is recommended, so attackers cannot decrypt the whole communication stream.

Authentication:

Anonymous (anon)

Anonymous key exchange:

Anonymous key exchanges are generally vulnerable to Man in the Middle attacks.

Encryption:

Advanced Encryption Standard with 128bit key in Cipher Block Chaining mode (AES 128 CBC)

Cipher Block Chaining:

The CBC mode is vulnerable to plain-text attacks with TLS 1.0, SSL 3.0 and lower. However a real fix is implemented with TLS 1.2 in which the GCM mode was introduced and which is not vulnerable to the BEAST attack. GCM should be preferred over CBC (cf. BEAST).

Hash:

Secure Hash Algorithm 1 (SHA)

Secure Hash Algorithm 1 MAC:

The Secure Hash Algorithm 1 has been proven to be vulnerable to collision attacks as of 2017 (cf. shattered.io). While this does not affect its usage as a MAC, safer alternatives such as SHA-256, or SHA-3 should be considered.

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Included in RFC:

• RFC 8422

Machine-readable:

application/json