Markdown Explorer 0.1.1 - Persistent Cross-Site Scripting

# Exploit Title: Markdown Explorer 0.1.1 - XSS to RCE
# Exploit Author: TaurusOmar
# Date: 04/05/2021
# CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
# Risk: High (8.8)
# Vendor Homepage: https://github.com/jersou/markdown-explorer
# Version: 0.1.1
# Tested on: Windows, Linux, MacOs

# Software Description:
Easily explore, view and edit markdown documentation of a file tree.
If your projects documentation is written in Markdown, with md files dispersed throughout your project tree, Markdown Explorer displays md files in a tree structure, and it allows filtering by file name or by file content.
Just drop a folder on the window (or click on the folder icon on top left) to show the Markdown documentation of this folder. Then, explore the tree on the left, and toggle view/edit mode on md file with the button on the top right.


# Vulnerability Description:
The software allows you to store payloads within its own editor, as well as upload (.md) files once malicious code is entered, the payload will be executed immediately.
The attacker can send a malicious file with the payload, when this file is opened, the chain will be executed successfully giving access to
the remote attacker to get remote execution on the computer.


#Proof
https://imgur.com/a/w4bcPWs



# Payload : exec(Attacker Reverse netcat stolen => /etc/passwd) && exec(calc)

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