Exploit Title: FoF Pretty Mail 1.1.2 Extension for Flarum Local File
Inclusion (LFI)
Date: 03/28/2024
Exploit Author: Chokri Hammedi
Vendor Homepage: https://flarum.org/
Software Link: https://github.com/FriendsOfFlarum/pretty-mail
Version: 1.1.2
Tested on: Windows XP
CVE: N/A
Description:

The FoF Pretty Mail extension for Flarum is vulnerable to Local File
Inclusion (LFI) due to the unsafe handling of file paths in the email
template. An attacker with administrative access can exploit this
vulnerability to include sensitive files from the server's file system in
the email content, potentially leading to information disclosure.

Steps to Reproduce:

Log in as an administrator on the Flarum forum.

Navigate to the FoF Pretty Mail extension settings.

Edit the email default template and insert the following payload at the end
of the template:

{{ include('/etc/passwd') }}

Save the changes to the email template.

Trigger any action that sends an email, such as user registration or
password reset.

The recipient of the email will see the contents of the included file (in
this case, /etc/passwd) in the email content.