Security always plays an important role in the communication. Steganography, which conceals the process of communication, is another efficient way to achieve secure communication besides encryption. This paper proposes a secure steganography scheme in JPEG images with high embedding capacity and low distortion to the cover image. It embeds the additional information by modifying the DCT coefficients in JPEG images. Considering the size of the additional information, some DCT coefficients are adaptively selected in the embedding process. Two chaotic encryption strategies are designed based on the hyper-chaotic system to encrypt the additional information before the embedding to enhance the security. Extensive experiments have demonstrated the validity and efficiency of this proposed scheme. Compared with some existing schemes, it offers larger embedding rate and lower distortion with stronger security.