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Following is my apache ssl protocol and cipher configuration

SSLEngine on  
SSLProtocol all -SSLv2  
SSLCipherSuite HIGH:MEDIUM:-SSLv2:!ADH

When tested on IE9 with TLS1.2 checkbox checked in browser settings, ssl protocol and cipher suite for the request is logged as TLSv1.2 DHE-RSA-AES256-GCM-SHA384 in ssl_request_log.

When I disable TLS1.2 in IE9, still the same protocol TLSv1.2 and cipher DHE-RSA-AES256-GCM-SHA384 is logged.

For all request if I enable /disable TLS1.2, same protocol and cipher is used.

How does IE communicates the supported cipher when TLS1.2 is enabled and disabled? why the same cipher /protocol used even if TLS1.2 is disabled?

EDIT

TLS1.2 Enabled

A SSLv3-compatible ClientHello handshake was found. Fiddler extracted the parameters below.

Major Version: 3
Minor Version: 3
Random: 55 53 44 E1 A0 D5 30 4E EF 6F 2E 83 79 63 70 07 DC 58 3C F4 C1 D6 6E 44 F0 83 6C 2F 6C 6E D2 06
SessionID: 00 27 00 00 56 EC 3A 1F C1 CF D8 D2 F5 D1 C8 78 B6 1C AE 6C 9C 1C 38 38 1D 1C D7 BF D1 CB B5 39
Ciphers: 
    [C028]  TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384
    [C027]  TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256
    [C014]  TLS1_CK_ECDHE_RSA_WITH_AES_256_CBC_SHA
    [C013]  TLS1_CK_ECDHE_RSA_WITH_AES_128_CBC_SHA
    [009F]  Unrecognized cipher - 
    [009E]  Unrecognized cipher - 
    [009D]  Unrecognized cipher - 
    [009C]  Unrecognized cipher - 
    [003D]  TLS_RSA_WITH_AES_256_CBC_SHA256
    [003C]  TLS_RSA_WITH_AES_128_CBC_SHA256
    [0035]  TLS_RSA_AES_256_SHA
    [002F]  TLS_RSA_AES_128_SHA
    [C02C]  TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384
    [C02B]  TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256
    [C024]  TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384
    [C023]  TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256
    [C00A]  TLS1_CK_ECDHE_ECDSA_WITH_AES_256_CBC_SHA
    [C009]  TLS1_CK_ECDHE_ECDSA_WITH_AES_128_CBC_SHA
    [006A]  TLS_DHE_DSS_WITH_AES_256_CBC_SHA256
    [0040]  TLS_DHE_DSS_WITH_AES_128_CBC_SHA256
    [0038]  TLS_DHE_DSS_WITH_AES_256_SHA
    [0032]  TLS_DHE_DSS_WITH_AES_128_SHA
    [000A]  SSL_RSA_WITH_3DES_EDE_SHA
    [0013]  SSL_DHE_DSS_WITH_3DES_EDE_SHA
    [0005]  SSL_RSA_WITH_RC4_128_SHA
    [0004]  SSL_RSA_WITH_RC4_128_MD5

Compression: 
    [00]    NO_COMPRESSION

Extensions: 
    renegotiation_info  00
    status_request  01 00 00 00 00
    elliptic_curves 00 06 00 17 00 18 00 19
    ec_point_formats    01 00
    signature_algorithms    00 12 04 01 05 01 06 01 02 01 04 03 05 03 06 03 02 03 02 02

TLS1.2 disabled

A SSLv3-compatible ClientHello handshake was found. Fiddler extracted the parameters below.

Major Version: 3
Minor Version: 2
Random: 55 53 45 D5 DA 1E 9D FC 6B C6 09 40 C4 E3 83 9C 38 3D 90 88 93 9C 4F 8B 97 6A BB 23 A6 60 95 12
SessionID: empty
Ciphers: 
    [C014]  TLS1_CK_ECDHE_RSA_WITH_AES_256_CBC_SHA
    [C013]  TLS1_CK_ECDHE_RSA_WITH_AES_128_CBC_SHA
    [0035]  TLS_RSA_AES_256_SHA
    [002F]  TLS_RSA_AES_128_SHA
    [C00A]  TLS1_CK_ECDHE_ECDSA_WITH_AES_256_CBC_SHA
    [C009]  TLS1_CK_ECDHE_ECDSA_WITH_AES_128_CBC_SHA
    [0038]  TLS_DHE_DSS_WITH_AES_256_SHA
    [0032]  TLS_DHE_DSS_WITH_AES_128_SHA
    [000A]  SSL_RSA_WITH_3DES_EDE_SHA
    [0013]  SSL_DHE_DSS_WITH_3DES_EDE_SHA
    [0005]  SSL_RSA_WITH_RC4_128_SHA
    [0004]  SSL_RSA_WITH_RC4_128_MD5

Compression: 
    [00]    NO_COMPRESSION

Extensions: 
    renegotiation_info  00
    status_request  01 00 00 00 00
    elliptic_curves 00 06 00 17 00 18 00 19
    ec_point_formats    01 00

I am not able to understand these cipher suites and come to a conclusion.

  • 2
    Grab a packet capture and look at the CLIENT HELLO (which is unencrypted). I think you'll find that IE9 is willing to talk TLS 1.2 even when you tell it not to. – gowenfawr May 12 '15 at 15:33
  • I'm lost as to why you're trying to *disable* TLS 1.2? You should be killing off all versions of SSL, and preferably also TLS 1.0, instead. – Iszi May 14 '15 at 20:03

0 Answers0