HTB academy intro to assembly language skills assessment # 1

Hello.

i have completed almost all task in this module. Only this one is missing to resolve. Please i need help.

The execise is this:

Disassemble ‘loaded_shellcode’ and modify its assembly code to decode the shellcode, by adding a loop to ‘xor’ each 8-bytes on the stack with the key in ‘rbx’.

i have used this code:

global _start

section .text

_start:

mov rax,0xa284ee5c7cde4bd7

push rax

mov rax,0x935add110510849a

push rax

mov rax,0x10b29a9dab697500

push rax

mov rax,0x200ce3eb0d96459a

push rax

mov rax,0xe64c30e305108462

push rax

mov rax,0x69cd355c7c3e0c51

push rax

mov rax,0x65659a2584a185d6

push rax

mov rax,0x69ff00506c6c5000

push rax

mov rax,0x3127e434aa505681

push rax

mov rax,0x6af2a5571e69ff48

push rax

mov rax,0x6d179aaff20709e6

push rax

mov rax,0x9ae3f152315bf1c9

push rax

mov rax,0x373ab4bb0900179a

push rax

mov rax,0x69751244059aa2a3

push rax

mov rbx,0x2144d2144d2144d2

mov rcx, 14

lea rdx, [rsp]

loopfun:

xor [rdx], rbx

add rdx, 8

loop loopfun

but i dont know what to do. I have debbuged but i dont see any flag.

Please help. Only need to resolve this to finish SOC prerequisite path and begin SOC analyst path.

Best regards

Hi! Have you solved it? I´m stucked too.

Help me please. I don’t know how solve it

check this:

https://www.reddit.com/r/hackthebox/comments/1buz9hv/htb_academy_intro_to_assembly_language_skills/

I don’t understand.

My code:

global _start

section .text

_start:
mov rax, 0xa284ee5c7cde4bd7
push rax
mov rax, 0x935add110510849a
push rax
mov rax, 0x10b29a9dab697500
push rax
mov rax, 0x200ce3eb0d96459a
push rax
mov rax, 0xe64c30e305108462
push rax
mov rax, 0x69cd355c7c3e0c51
push rax
mov rax, 0x65659a2584a185d6
push rax
mov rax, 0x69ff00506c6c5000
push rax
mov rax, 0x3127e434aa505681
push rax
mov rax, 0x6af2a5571e69ff48
push rax
mov rax, 0x6d179aaff20709e6
push rax
mov rax, 0x9ae3f152315bf1c9
push rax
mov rax, 0x373ab4bb0900179a
push rax
mov rax, 0x69751244059aa2a3
push rax
mov rbx, 0x2144d2144d2144d2
mov rcx, 15
mov rdx, rsp
_loop:
xor qword [rdx], rbx
add rdx, 8
loop _loop
call rsp
mov rax, 60
syscall
I decoded shellcode and run it

i dont remember how to solved. all i know it those links can help you. sorry.