Undetected

Verified writeups for the Undetected machine of Hack The Box

Undetected

$ tldr PHPUnit (CVE-2017-9841) RCE → Apache backdoor binary analysis

CVE / Bulletins: CVE-2017-9841 ↗

·	·
Operating system	Linux
Difficulty	Medium
Vector	Linux privesc
IP	10.10.11.146
Retirement date	2022-07-02
Skills	Virtual Hosting Enumeration Abusing Directory Listing PHPUnit 5.6 Exploitation (CVE-2017-9841) [RCE] Backup Inspection Binary Analysis - GHIDRA Cracking Hashes Apache Backdoor Analysis [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
Subdomain Enumeration	HackTricks	Open
Cracking Hashes (hashcat / John)	HackTricks	Open
Remote Code Execution (RCE)	HackTricks	Open

Related skills worth mastering

Brute Force / Rate-Limit Bypass · Local File Inclusion (LFI) · Remote File Inclusion (RFI) · Shellshock (CVE-2014-6271)

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Last updated: 2026-06-07