  In this work, the problem of transmitting an i.i.d Gaussian source over an
i.i.d Gaussian wiretap channel with an i.i.d Gaussian side information
available at the intended receiver is considered. The intended receiver is
assumed to have a certain minimum SNR and the eavesdropper is assumed to have a
strictly lower SNR, compared to the intended receiver. The objective is to
minimize the distortion of source reconstruction at the intended receiver. In
this work, it is shown that the source-channel separation coding scheme is
optimum in the sense of achieving minimum distortion. Two hybrid digital-analog
Wyner-Ziv coding schemes are then proposed which achieve the minimum
distortion. These secure joint source-channel coding schemes are based on the
Wyner-Ziv coding scheme and wiretap channel coding scheme when the analog
source is not explicitly quantized. The proposed secure hybrid digital-analog
schemes are analyzed under the main channel SNR mismatch. It is proven that the
proposed schemes can give a graceful degradation of distortion with SNR under
SNR mismatch, i.e., when the actual SNR is larger than the designed SNR.
