Insecure TLS_RSA_WITH_RC4_128_MD5

IANA name:

TLS_RSA_WITH_RC4_128_MD5

GnuTLS name:

TLS_RSA_ARCFOUR_128_MD5

Hex code:

0x00, 0x04

TLS Version(s):

TLS1.0, TLS1.1, TLS1.2, TLS1.3

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Protocol:

Transport Layer Security (TLS)

Key Exchange:

Rivest Shamir Adleman algorithm (RSA)

Non-ephemeral Key Exchange:

This key exchange algorithm does not support Perfect Forward Secrecy (PFS) which is recommended, so attackers cannot decrypt the complete communication stream.

Authentication:

Rivest Shamir Adleman algorithm (RSA)

RSA Authentication:

There are reports that servers using the RSA authentication algorithm with keys longer than 3072-bit may experience heavy performance issues leading to connection timeouts and even service unavailability if many clients open simultaneous connections.

Encryption:

Rivest Cipher 4 with 128bit key (RC4 128)

Rivest Cipher 4:

IETF has officially prohibited RC4 for use in TLS in RFC 7465. Therefore, it can be considered insecure.

Hash:

HMAC Message Digest 5 (MD5)

Message Digest 5:

The Message Digest 5 algorithm suffers form multiple vulnerabilities and is considered insecure.

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Included in RFC:

• RFC 5246

Machine-readable:

application/json