In the previous section, we have seen how to make use of various encoders in order to make our payload undetectable from antivirus programs. However, even after using different encoders and iterations, our payload was still detected by a few antivirus programs. In order to make our payload completely stealthy, we can make use of a called encrypted self extracting archive feature offered by a compression utility called 7-Zip.
To begin, we'll first upload a malicious PDF file (containing a payload) to the site http://www.virustotal.com, as shown in the following screenshot. The analysis shows that our PDF file was detected by 32 antivirus programs out of the 56 available, as seen in the following screenshot: