Hi, After some debate with Microsoft, they have directed me to the following text ( http://www.ietf.org/rfc/rfc2246.txt?number=2246 ): "Note: An attack discovered by Daniel Bleichenbacher [BLEI] can be used to attack a TLS server which is using PKCS#1 encoded RSA. The attack takes advantage of the fact that by failing in different ways, a TLS server can be coerced into revealing whether a particular message, when decrypted, is properly PKCS#1 formatted or not.
The best way to avoid vulnerability to this attack is to treat incorrectly formatted messages in a manner indistinguishable from correctly formatted RSA blocks. Thus, when it receives an incorrectly formatted RSA block, a server should generate a random 48-byte value and proceed using it as the premaster secret. Thus, the server will act identically whether the received RSA block is correctly encoded or not." Therefore IIS will received the bogus key created for OpenSSL and will reply to it even though its incorrect in its size. Therefore it will create a false positive. I have created a patch for this that will hopefully redeem this vulnerability. The patch also creates a sub function whereby changing the debug = 0 to debug = 1 you can process the results you receive. Thanks Noam Rathaus CTO Beyond Security Ltd http://www.SecurITeam.com http://www.BeyondSecurity.com
openssl_overflow_generic_test.patch
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