Network Security Assessment, 3rd Edition

Appendix C. Unsafe TLS Cipher Suites

TLS implementations are often found to support weak cipher suites. Adversaries with network access can exploit vulnerabilities within these to decrypt ciphertext via man-in-the-middle in particular. The suites listed in Tables C-1 through C-3 lack authentication (anonymous ciphers), perform symmetric encryption using no key (null ciphers), and operate in an exploitable manner (export-grade ciphers). As such, they should be avoided and not exist within modern environments.

Table C-1. TLS anonymous cipher suites

Code	Name	Code	Name
0x0017	TLS_DH_Anon_EXPORT_WITH_RC4_40_MD5	0x0089	TLS_DH_Anon_WITH_CAMELLIA_256_CBC_SHA
0x0018	TLS_DH_Anon_WITH_RC4_128_MD5	0x009B	TLS_DH_Anon_WITH_SEED_CBC_SHA
0x0019	TLS_DH_Anon_EXPORT_WITH_DES40_CBC_SHA	0x00A6	TLS_DH_Anon_WITH_AES_128_GCM_SHA256
0x001A	TLS_DH_Anon_WITH_DES_CBC_SHA	0x00A7	TLS_DH_Anon_WITH_AES_256_GCM_SHA384
0x001B	TLS_DH_Anon_WITH_3DES_EDE_CBC_SHA	0xC015	TLS_ECDH_Anon_WITH_NULL_SHA
0x0034	TLS_DH_Anon_WITH_AES_128_CBC_SHA	0xC016	TLS_ECDH_Anon_WITH_RC4_128_SHA
0x003A	TLS_DH_Anon_WITH_AES_256_CBC_SHA	0xC017	TLS_ECDH_Anon_WITH_3DES_EDE_CBC_SHA
0x0046	TLS_DH_Anon_WITH_CAMELLIA_128_CBC_SHA	0xC018	TLS_ECDH_Anon_WITH_AES_128_CBC_SHA
0x006C	TLS_DH_Anon_WITH_AES_128_CBC_SHA256	0xC019	TLS_ECDH_Anon_WITH_AES_256_CBC_SHA
0x006D	TLS_DH_Anon_WITH_AES_256_CBC_SHA256

Table C-2. TLS null cipher suites

Code	Name	Code	Name
0x0000	TLS_NULL_WITH_NULL_NULL	0x00B4	TLS_DHE_PSK_WITH_NULL_SHA256 ...