来源

关联漏洞

描述

:broken_heart: Hearbleed exploit to retrieve sensitive information CVE-2014-0160 :broken_heart:

介绍

Heartbleed PoC
===========

A sample example of the [Heartbleed](http://en.wikipedia.org/wiki/Heartbleed) attack using the server https://www.cloudflarechallenge.com/ made for trying this attack.

First, the two best explanations I read on the subject :
* http://www.seancassidy.me/diagnosis-of-the-openssl-heartbleed-bug.html 
* http://xkcd.com/1354/

## Exploit

The exploit start by sending the handshake to the server *cloudflarechallenge.com* to create the secure connection with tls. Then the function `hit_hb(s)` send a typycall heartbeat request :
```
hb = h2bin('''
18 03 02 00 03
01 40 00
''')
````

* Explanation of heartbeat (bf)call : <br>
    18      : hearbeat record  <br>
    03 02   : TLS version  <br>
    00 03   : length  <br>
    01      : hearbeat request  <br>
    40 00   : payload length 16 384 bytes check rfc6520  <br>
                "The total length of a HeartbeatMessage MUST NOT exceed 2^14"
                If we enter FF FF -> 65 535, we will received 4 paquets of length 16 384 bytes
                
We wait for the response of the server and then we unpack 5 bytes (the header) of the tls packet `(content_type, version, length) = struct.unpack('>BHH', hdr)`

After that we read the rest of the request due to the length we get from the header.
The data are stored in the file `òut.txt`.
                
**Note**: the attack can be [made in the handshake phase](http://security.stackexchange.com/a/55117/41351) before the encryption but for simplicity, this exploit start after the handshake. 

## Run it !

You must have python `2.7.*` installed on your computer (not tested on python 3)

```
python2 heartbleed-exploit.py www.cloudflarechallenge.com
```

Then you will see somehting like this :

![heartbleed](https://i.gyazo.com/ccd58098438eff4124bf1e9bb9776ae5.png)

Then you can check the file `out.txt` to see `2^14 (40 00)` of data contained in the memory of the serveur instead of 4 !
You can run the exploit many time, you will have different résult in the file. 

**/!\ WARNING** the file will be overwritten after each execution of the exploit

##Ressources and thanks

* http://en.wikipedia.org/wiki/Heartbleed
* https://github.com/Lekensteyn/pacemaker/blob/master/pacemaker.py#L19
* https://gist.github.com/sh1n0b1/10100394
* https://github.com/openssl/openssl/commit/96db9023b881d7cd9f379b0c154650d6c108e9a3
* https://hacking.ventures/rsa-keys-in-heartbleed-memory/

文件快照

 [4.0K]  /data/pocs/46e5786c798aa8f8ca6d9a2497e0242d27634410
├── [5.4K]  heartbleed-exploit.py
├── [2.4K]  README.md
└── [4.0K]  utils
    ├── [  85]  __init__.py
    └── [ 666]  pyfancy.py

1 directory, 4 files

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