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仅启用ECDHE的密码套件

[root@centos7 ~]#  openssl ciphers -V 'EECDH+CHACHA20:EECDH+CHACHA20-draft:EECDH+AES128:EECDH+AES256::!MD5' | nl
     1            0xC0,0x2F - ECDHE-RSA-AES128-GCM-SHA256 TLSv1.2 Kx=ECDH     Au=RSA  Enc=AESGCM(128) Mac=AEAD
     2            0xC0,0x2B - ECDHE-ECDSA-AES128-GCM-SHA256 TLSv1.2 Kx=ECDH     Au=ECDSA Enc=AESGCM(128) Mac=AEAD
     3            0xC0,0x27 - ECDHE-RSA-AES128-SHA256 TLSv1.2 Kx=ECDH     Au=RSA  Enc=AES(128)  Mac=SHA256
     4            0xC0,0x23 - ECDHE-ECDSA-AES128-SHA256 TLSv1.2 Kx=ECDH     Au=ECDSA Enc=AES(128)  Mac=SHA256
     5            0xC0,0x13 - ECDHE-RSA-AES128-SHA    SSLv3 Kx=ECDH     Au=RSA  Enc=AES(128)  Mac=SHA1
     6            0xC0,0x09 - ECDHE-ECDSA-AES128-SHA  SSLv3 Kx=ECDH     Au=ECDSA Enc=AES(128)  Mac=SHA1
     7            0xC0,0x30 - ECDHE-RSA-AES256-GCM-SHA384 TLSv1.2 Kx=ECDH     Au=RSA  Enc=AESGCM(256) Mac=AEAD
     8            0xC0,0x2C - ECDHE-ECDSA-AES256-GCM-SHA384 TLSv1.2 Kx=ECDH     Au=ECDSA Enc=AESGCM(256) Mac=AEAD
     9            0xC0,0x28 - ECDHE-RSA-AES256-SHA384 TLSv1.2 Kx=ECDH     Au=RSA  Enc=AES(256)  Mac=SHA384
    10            0xC0,0x24 - ECDHE-ECDSA-AES256-SHA384 TLSv1.2 Kx=ECDH     Au=ECDSA Enc=AES(256)  Mac=SHA384
    11            0xC0,0x14 - ECDHE-RSA-AES256-SHA    SSLv3 Kx=ECDH     Au=RSA  Enc=AES(256)  Mac=SHA1
    12            0xC0,0x0A - ECDHE-ECDSA-AES256-SHA  SSLv3 Kx=ECDH     Au=ECDSA Enc=AES(256)  Mac=SHA1

首先，我们介绍一下“允许SSL采用中强度加密”这个漏洞：远程主机支持SSL使用的密码采用中强度解密，即使用的KEY解密长度至少56位，但少于112位。如果攻击者在同一个物理网段，密码很容易暴露。
加固建议：避免使用中强度加密，改为强度较高的加密算法。
漏洞扫描信息：

Here is the list of medium strength SSL ciphers supported by the remote server :
  Medium Strength Ciphers (> 64-bit and < 112-bit key, or 3DES)
    ECDHE-RSA-DES-CBC3-SHA       Kx=ECDH        Au=RSA      Enc=3DES-CBC(168)        Mac=SHA1   
The fields above are :
  {OpenSSL ciphername}
  Kx={key exchange}
  Au={authentication}
  Enc={symmetric encryption method}
  Mac={message authentication code}
  {export flag}