6.D.4. Scanning the file using virustotal.com

asm_linx86_send-string-all-terminals_shellstorm_sample3_mod-alt

This file is not being flagged, good.

asm_linx86_send-string-all-terminals_shellstorm_sample3_mod-alt_jmpcallpop

Again, not being flagged.

asm_linx86_send-string-all-terminals_shellstorm_sample3_mod-alt_jmpcallpop-xor-c

Whoops! Something is going on, multiple vendors complain the file might be malicious. This is probably due to pattern matching signatures in AV/IDS products, which detect certain common XOR operations and flag them as malicious.