[RWCTF2021]wp
好像也一个题不会来着，其实算是个复现吧。。。
以及寒假+过年摸了好久的鱼。。。
Hack into Skynet
最多解的web，是一个加了一个迷之AI的pgsql注入
#!/usr/bin/env python3
import flask
import psycopg2
import datetime
import hashlib
from skynet import Skynet
app = flask.Flask(__name__, static_url_path='')
skynet = Skynet()
def skynet_detect():
req = {
'method': flask.request.method,
'path': flask.request.full_path,
'host': flask.request.headers.get('host'),
'content_type': flask.request.headers.get('content-type'),
'useragent': flask.request.headers.get('user-agent'),
'referer': flask.request.headers.get('referer'),
'cookie': flask.request.headers.get('cookie'),
'body': str(flask.request.get_data()),
}
_, result = skynet.classify(req)
return result and result['attack']
@app.route('/static/<path:path>')
def static_files(path):
return flask.send_from_directory('static', path)
@app.route('/', methods=['GET', 'POST'])
def do_query():
if skynet_detect():
return flask.abort(403)
if not query_login_state():
response = flask.make_response('No login, redirecting', 302)
response.location = flask.escape('/login')
return response
if flask.request.method == 'GET':
return flask.send_from_directory('', 'index.html')
elif flask.request.method == 'POST':
kt = query_kill_time()
if kt:
result = kt
else:
result = ''
return flask.render_template('index.html', result=result)
else:
return flask.abort(400)
@app.route('/login', methods=['GET', 'POST'])
def do_login():
if skynet_detect():
return flask.abort(403)
if flask.request.method == 'GET':
return flask.send_from_directory('static', 'login.html')
elif flask.request.method == 'POST':
if not query_login_attempt():
return flask.send_from_directory('static', 'login.html')
else:
session = create_session()
response = flask.make_response('Login success', 302)
response.set_cookie('SessionId', session)
response.location = flask.escape('/')
return response
else:
return flask.abort(400)
def query_login_state():
sid = flask.request.cookies.get('SessionId', '')
if not sid:
return False
now = datetime.datetime.now()
with psycopg2.connect(
host="challenge-db",
database="ctf",
user="ctf",
password="ctf") as conn:
cursor = conn.cursor()
cursor.execute("SELECT sessionid"
" FROM login_session"
" WHERE sessionid = %s"
" AND valid_since <= %s"
" AND valid_until >= %s"
"", (sid, now, now))
data = [r for r in cursor.fetchall()]
return bool(data)
def query_login_attempt():
username = flask.request.form.get('username', '')
password = flask.request.form.get('password', '')
if not username and not password:
return False
sql = ("SELECT id, account"
" FROM target_credentials"
" WHERE password = '{}'").format(hashlib.md5(password.encode()).hexdigest())
user = sql_exec(sql)
name = user[0][1] if user and user[0] and user[0][1] else ''
return name == username
def create_session():
valid_since = datetime.datetime.now()
valid_until = datetime.datetime.now() + datetime.timedelta(days=1)
sessionid = hashlib.md5((str(valid_since)+str(valid_until)+str(datetime.datetime.now())).encode()).hexdigest()
sql_exec_update(("INSERT INTO login_session (sessionid, valid_since, valid_until)"
" VALUES ('{}', '{}', '{}')").format(sessionid, valid_since, valid_until))
return sessionid
def query_kill_time():
name = flask.request.form.get('name', '')
if not name:
return None
sql = ("SELECT name, born"
" FROM target"
" WHERE age > 0"
" AND name = '{}'").format(name)
nb = sql_exec(sql)
if not nb:
return None
return '{}: {}'.format(*nb[0])
def sql_exec(stmt):
data = list()
try:
with psycopg2.connect(
host="challenge-db",
database="ctf",
user="ctf",
password="ctf") as conn:
cursor = conn.cursor()
cursor.execute(stmt)
for row in cursor.fetchall():
data.append([col for col in row])
cursor.close()
except Exception as e:
print(e)
return data
def sql_exec_update(stmt):
data = list()
try:
with psycopg2.connect(
host="challenge-db",
database="ctf",
user="ctf",
password="ctf") as conn:
cursor = conn.cursor()
cursor.execute(stmt)
conn.commit()
except Exception as e:
print(e)
return data
if __name__ == "__main__":
app.run(host='0.0.0.0', port=8080)