Basics

Educational purposes only

These notes are written strictly for CTF (Capture The Flag) challenges and educational learning. Do not use these techniques against systems you do not own or have explicit written permission to test. The author does not endorse or support any illegal or unauthorized activity.

Top ports

# FTP 21
# SSH 22
# HTTP 80
# Windows NETBIOS 139
# HTTPS 443
# SMB 445

TCP/IP Fondamentals

# Client send "SYN" request to Server

# if connection opened
# Server answer with "SYN/ACK" request
# Client answer with "ACK" request

# if connection closed
# Client send SYN request to Server
# Server answer with RST request

Interresting files

.htaccess
robots.txt
.DS_Store
css & javascript
.well-known/security.txt

# LFI
/var/log/apache2/error.log
/var/log/apache2/access.log
/.dockerenv
/etc/php/8.2/apache2/php.ini
/etc/php/8.2/cli/php.ini

Read files using Python instance

print open("/root/ETSCTF", "r").read()
print open("/etc/passwd", "r").read()
print open("/etc/shadow", "r").read()