Qt 5.12.2 through 5.14.2 as used in unofficial builds of Mumble 1.3.0 and other products mishandles OpenSSL's error queue which can cause a denial of service to QSslSocket users. Because errors leak in unrelated TLS sessions an unrelated session may be disconnected when any handshake fails. (Mumble 1.3.1 is not affected regardless of the Qt version.)

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