BackendTwo

Verified writeups for the BackendTwo machine of Hack The Box

BackendTwo

$ tldr FastAPI mass assignment → JWT forge → pam_wordle privesc

·	·
Operating system	Linux
Difficulty	Medium
Vector	Web
IP	10.10.11.162
Retirement date	2022-05-02
Skills	API Enumeration Abusing API - Registering a user Accessing the Docs path of FastAPI Mass Assignment Attack (Becoming superusers) Abusing API - Reading system files Information Leakage Forge JWT (Assigning us an extra privilege) Abusing API - Creating a new file to achieve remote command execution (RCE) Abusing pam_wordle (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
Information Leakage	HackTricks	Open
Remote Code Execution (RCE)	HackTricks	Open
JSON Web Tokens (JWT)	PortSwigger	Open

Related skills worth mastering

Local File Inclusion (LFI) · Remote File Inclusion (RFI) · Shellshock (CVE-2014-6271)

If you liked this machine, try

• Backend — Linux, Medium
• Seal — Linux, Medium
• Frolic — Linux, Easy
• Curling — Windows, Easy
• Remote — Windows, Easy

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Last updated: 2026-06-07