| Description: | If an application encounters a fatal protocol error and then calls
SSL_shutdown() twice (once to send a close_notify, and once to receive
one) then OpenSSL can respond differently to the calling application
if a 0 byte record is received with invalid padding compared to if a 0
byte record is received with an invalid MAC. If the application then
behaves differently based on that in a way that is detectable to the
remote peer, then this amounts to a padding oracle that could be used
to decrypt data. In order for this to be exploitable "non-stitched"
ciphersuites must be in use. Stitched ciphersuites are optimised
implementations of certain commonly used ciphersuites. Also the
application must call SSL_shutdown() twice even if a protocol error
has occurred (applications should not do this but some do anyway).
Fixed in OpenSSL 1.0.2r (Affected 1.0.2-1.0.2q).
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