Schooled

Verified writeups for the Schooled machine of Hack The Box

Schooled

$ tldr Moodle stored XSS → CVE-2020-14321 manager → plugin install RCE

CVE / Bulletins: CVE-2020-14321 ↗

·	·
Operating system	Linux
Difficulty	Medium
Vector	Web
IP	10.10.10.234
Retirement date	2021-09-11
Skills	VHost Brute Force Moodle Enumeration Moodle - Stored XSS Stealing a teacher’s session cookie Privilege escalation from teacher role into manager role to RCE [CVE-2020-14321] Elevating our privilege to Manager in Moodle - User Impersonation Mass Assignment Attack - Enable Full Permissions Giving us the ability to install a plugin Achieving remote command execution through installation of a malicious Plugin Enumerating the database once we have gained access to the system Cracking Hashes Abusing sudoers privilege (pkg install package) [Privilege Escalation]

Writeups

Language	Author	Format	Link
🇪🇸 ES	S4vitar	Vídeo	Open
🇬🇧 EN	0xdf	Texto	Open
🇬🇧 EN	IppSec	Vídeo	Open

Skill resources

Curated documentation for each technique listed in the Skills column above. Sources: HackTricks, GTFOBins, PortSwigger, etc.

Skill	Source	Link
Cracking Hashes (hashcat / John)	HackTricks	Open
Remote Code Execution (RCE)	HackTricks	Open
Cross-Site Scripting (XSS)	HackTricks	Open
Cross-Site Scripting (XSS)	PortSwigger	Open

Related skills worth mastering

Local File Inclusion (LFI) · Remote File Inclusion (RFI) · Shellshock (CVE-2014-6271) · SQL Injection · Server-Side Request Forgery

If you liked this machine, try

• Undetected — Linux, Medium
• CrossFit — Linux, Insane
• Holiday — Linux, Hard
• Joker — Linux, Hard
• Stacked — Linux, Insane

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Last updated: 2026-06-07