Weak Cipher Suite

IANA name:

TLS_KRB5_WITH_3DES_EDE_CBC_SHA

Hex code:

0x00, 0x1F

TLS Version(s):

TLS1.0, TLS1.1

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Protocol:

Transport Layer Security (TLS)

Key Exchange:

Kerberos 5 (KRB5)

Authentication:

Kerberos 5 (KRB5)

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 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 2712

Machine-readable:

application/json