hacktricks/pentesting-web/deserialization/basic-java-deserialization-objectinputstream-readobject.md

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Katika chapisho hili, mfano utaelezwa ukitumia `java.io.Serializable`.

# Serializable

Kiolesura cha Java `Serializable` (`java.io.Serializable` ni kiolesura cha alama ambacho darasa zako lazima zitekeleze ikiwa zinapaswa **kuserilishwa** na **kudiserilishwa**. Userilishaji wa vitu vya Java (kuandika) unafanywa na [ObjectOutputStream](http://tutorials.jenkov.com/java-io/objectoutputstream.html) na kudiserilishwa (kusoma) unafanywa na [ObjectInputStream](http://tutorials.jenkov.com/java-io/objectinputstream.html).

Hebu tuone mfano na **darasa la Person** ambalo ni **linaloweza kuserilishwa**. Darasa hili **linabadilisha kazi ya readObject**, kwa hivyo wakati **kitu chochote** cha darasa hili **kinapodiserilishwa**, **kazi hii** itatekelezwa.\
Katika mfano huo, kazi ya **readObject** ya darasa la Person inaita kazi `eat()` ya mnyama wake na kazi `eat()` ya Mbwa (kwa sababu fulani) inaita **calc.exe**. **Tutaona jinsi ya kuserilisha na kudiserilisha kitu cha Person ili kutekeleza kikokotozi hiki:**

**Mfano ufuatao ni kutoka [https://medium.com/@knownsec404team/java-deserialization-tool-gadgetinspector-first-glimpse-74e99e493649](https://medium.com/@knownsec404team/java-deserialization-tool-gadgetinspector-first-glimpse-74e99e493649)**
```java
import java.io.Serializable;
import java.io.*;

public class TestDeserialization {
interface Animal {
public void eat();
}
//Class must implements Serializable to be serializable
public static class Cat implements Animal,Serializable {
@Override
public void eat() {
System.out.println("cat eat fish");
}
}
//Class must implements Serializable to be serializable
public static class Dog implements Animal,Serializable {
@Override
public void eat() {
try {
Runtime.getRuntime().exec("calc");
} catch (IOException e) {
e.printStackTrace();
}
System.out.println("dog eat bone");
}
}
//Class must implements Serializable to be serializable
public static class Person implements Serializable {
private Animal pet;
public Person(Animal pet){
this.pet = pet;
}
//readObject implementation, will call the readObject from ObjectInputStream  and then call pet.eat()
private void readObject(java.io.ObjectInputStream stream)
throws IOException, ClassNotFoundException {
pet = (Animal) stream.readObject();
pet.eat();
}
}
public static void GeneratePayload(Object instance, String file)
throws Exception {
//Serialize the constructed payload and write it to the file
File f = new File(file);
ObjectOutputStream out = new ObjectOutputStream(new FileOutputStream(f));
out.writeObject(instance);
out.flush();
out.close();
}
public static void payloadTest(String file) throws Exception {
//Read the written payload and deserialize it
ObjectInputStream in = new ObjectInputStream(new FileInputStream(file));
Object obj = in.readObject();
System.out.println(obj);
in.close();
}
public static void main(String[] args) throws Exception {
// Example to call Person with a Dog
Animal animal = new Dog();
Person person = new Person(animal);
GeneratePayload(person,"test.ser");
payloadTest("test.ser");
// Example to call Person with a Cat
//Animal animal = new Cat();
//Person person = new Person(animal);
//GeneratePayload(person,"test.ser");
//payloadTest("test.ser");
}
}
```
## Hitimisho

Kama unavyoona katika mfano huu wa msingi sana, "udhaifu" hapa unaonekana kwa sababu **kazi ya readObject** inaita **kazi nyingine zenye udhaifu**.


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<summary><strong>Jifunze kuhusu kudukua AWS 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>

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* Ikiwa unataka kuona **kampuni yako inatangazwa katika HackTricks** au **kupakua HackTricks kwa muundo wa PDF** Angalia [**MPANGO WA KUJIUNGA**](https://github.com/sponsors/carlospolop)!
* Pata [**swag rasmi ya PEASS & HackTricks**](https://peass.creator-spring.com)
* Gundua [**Familia ya PEASS**](https://opensea.io/collection/the-peass-family), mkusanyiko wetu wa [**NFTs**](https://opensea.io/collection/the-peass-family) ya kipekee
* **Jiunge na** 💬 [**Kikundi cha Discord**](https://discord.gg/hRep4RUj7f) au [**kikundi cha telegram**](https://t.me/peass) au **tufuate** kwenye **Twitter** 🐦 [**@carlospolopm**](https://twitter.com/hacktricks_live)**.**
* **Shiriki mbinu zako za kudukua kwa kuwasilisha PR kwa** [**HackTricks**](https://github.com/carlospolop/hacktricks) na [**HackTricks Cloud**](https://github.com/carlospolop/hacktricks-cloud) repos za github.

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