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DHE (Diffie-Hellman Ephemeral)
Ephemeral Diffie-Hellman[405][406][407][408] is a variant of Diffie-Hellman[99][100][101][102][103] key exchange[133] protocol that has forward secrecy[127][128][129][130], and does protect past sessions against future compromises. If long-term secret keys or passwords are compromised, encrypted communications and sessions recorded in the past cannot be retrieved and decrypted. However, there is a protocol flaw called D(HE)at attack[581][582][583][584][585], a denial-of-service attack[586][587][588][589][590], which can be exploited effectively when large key sizes are enabled.
Always prefer cipher suites with PFS property over the non-PFS ones. Note that performance considerations implies preferring Ephemeral Elliptic-curve Diffie–Hellman[432][433] over Ephemeral Diffie-Hellman[405][406][407][408] and D(HE)at attack[581][582][583][584][585] implies using Diffie-Hellman ephemeral public key parameter[409][410][411]s with a size greater or equal than 2048 bits but less or equal than 4096 bits.
PSK
The pre-shared key[160] can ensure authenticity[75][76][77] of the communicating parties mutually based on symmetric key[185][186][187]s that are shared in advance among the parties. Combined with a key exchange[133] that has forward secrecy[127][128][129][130] property algorithm can protect against dictionary attack[58][59]s by passive eavesdroppers (but not active attackers). Pre-shared keys with low entropy[126], may caused by a weakness[171][172][173] of random number generator[168][169][170], can be easily broken in brute-force attack[54]. Leading client applications do not use this algorithm. Unless your application or requirements specifically call for their use, it is generally safer to avoid cipher suites that are not adopted and supported by a critical mass of the industry.
If your application or requirements specifically call for the use of algorithms which are not used by the leading client applications set the cipher suite order explicitly and cipher suites used by the leading client applications be preferred over the ones which do not used by them.
Camellia-128
Encryption algorithm Camellia[318][319][320][321] is a block cipher[78][79][80][81] which is considered secure[322][323], but leading client applications do not use this algorithm. Unless your application or requirements specifically call for their use, it is generally safer to avoid cipher suites that are not adopted and supported by a critical mass of the industry.
Remove the cipher suite from the list of cipher suites supported by your server.
CBC
Encryption mode is cipher block chaining[28][29][30]. It is vulnerable[31] to timing attack[188] (eg: Lucky Thirteen attack[11][12]) and padding oracle attack[63][64][65][66] (eg: POODLE attack[13][14][15]).
Remove the cipher suite from the list of cipher suites supported by your server or at least set the cipher suite order explicitly and any cipher suite modes be preferred over ciphers suites with CBC modes.
128
The symmetric key[185][186][187] withkey size[184] more than 128 bits as it is should be according to National Institute of Standards and Technology[470][471] so it is not vulnerable to preimage attack[67] and it cannreliably prove that message came from the stated sender (its authenticity) and has not been changed, so connection is not open for a man-in-the-middle attack[61].
Remove the cipher suite from the list of cipher suites supported by your server.
SHA2-256
message authentication code[135][136][137][138] is a hashed message authentication code[139][140][141][142][143][144][145] which is considered secure. The underlaying cryptographic hash function[94][95][96][97] (Secure Hash Algorithm 2[212][213][214]) is also considered secure.
If your application or requirements specifically call for the use of a message authentication code[135][136][137][138] that does not provide authenticated encryption[74] prefer block cipher mode of operation[82][83][84][85][86] (eg: counter with CBC-MAC[32][33][34], Galois/Counter Mode[46][47][48][49] or message authentication code[135][136][137][138] (eg: Poly1305[458][459]) that proved authenticated encryption over the ones which does not provide it. In case of a hashed message authentication code[139][140][141][142][143][144][145] prefer message authentication code[135][136][137][138] based on Secure Hash Algorithm 2[212][213][214] over the ones based on Secure Hash Algorithm 1[202][203][204].
