Insecure Cipher Suite

IANA name:

TLS_DH_anon_WITH_3DES_EDE_CBC_SHA

OpenSSL name:

ADH-DES-CBC3-SHA

GnuTLS name:

TLS_DH_ANON_3DES_EDE_CBC_SHA1

Hex code:

0x00, 0x1B

TLS Version(s):

TLS1.0, TLS1.1

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Protocol:

Transport Layer Security (TLS)

Key Exchange:

Diffie-Hellman (DH)

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:

Triple-DES (Encrypt Decrypt Encrypt) in Cipher Block Chaining mode (3DES EDE 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).

Triple-DES:

While Triple-DES is still recognized as a secure symmetric-key encryption, a more and more standardizations bodies and projects decide to deprecate this algorithm. Though not broken, it has been proven to suffer from several vulnerabilities in the past (cf. Sweet32).

Hash:

Secure Hash Algorithm 1 (SHA)

Secure Hash Algorithm 1 MAC:

The Secure Hash Algorithm 1 has been proven to be vulnerable to chosen-prefix collision attacks as of 2019 (cf. sha-mbles.github.io). While this does not affect its usage as a MAC, safer alternatives such as SHA-256, or SHA-3 should be considered.

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 5246

Machine-readable:

application/json