  Due to the vital role of security in online communications and this fact that
attackers are developing their tools, modernizing the security tools is an
essential. The efficiency of crypto systems has been proven after years,
however one may need to communicate stealthy without drawing attention
especially in transferring secret data such as keys. Covert channels are
suitable tools that used to conceal the existence of data besides end
communication parties by employing principles of steganography. They can make
secure communications with obscurity. Working stealthy and providing an
acceptable throughput are issues in designing covert channels. The DNS protocol
properties like its necessity for running applications and the availability can
provide aforementioned issues decently. In this paper, we proposed a storage
covert channel which uses DNS protocol as a media for transferring data. The
key features include connection establishment, adaptability with network
environment, implying a lightweight obfuscation method and HMAC to meet
confidentiality and integrity. Experimental results show the proposed channel
statistics are well adapted with normal traffics. The channel has an average
capacity of 2.65 bytes of data per packet.
