Feline

Verified writeups for the Feline machine of Hack The Box

Feline

$ tldr Tomcat ysoserial deser → SaltStack CVE-2020-1651 → docker.sock

CVE / Bulletins: CVE-2020-9484 ↗ CVE-2020-1651 ↗

·	·
Operating system	Linux
Difficulty	Hard
Vector	Web
IP	10.10.10.205
Retirement date	2021-02-20
Skills	Information leakage in error message RCE by deserialization in Apache Tomcat with PersistentManager - CVE-2020-9484 [RCE] Playing with Ysoserial - CommonsCollections2 Manipulating our session cookie (JSESSIONID) + Directory Path Traversal Playing with chisel [Socks Proxy + Proxychains (socks5)] SaltStack Exploitation - CVE-2020-1651 Gaining root access to a container Playing with docker.sock file + Abusing Docker API [Privilege Escalation] PIVOTING

Writeups

Language	Author	Format	Link
🇪🇸 ES	S4vitar	Vídeo	Open
🇪🇸 ES	El Pingüino de Mario	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
Insecure Deserialization	PortSwigger	Open
Directory / Path Traversal	PortSwigger	Open
Port Forwarding / Pivoting	HackTricks	Open
Remote Code Execution (RCE)	HackTricks	Open

Related skills worth mastering

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

If you liked this machine, try

• Talkative — Linux, Hard
• Jewel — Linux, Medium
• Laboratory — Linux, Easy
• Monitors — Linux, Hard
• Oouch — Linux, Hard

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Last updated: 2026-06-07