Top 5 Pentesting Commands That Hackers Use Daily – And How to Stop Them + Video

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Introduction:

In the ever-evolving landscape of cybersecurity, a single misconfigured firewall or an overlooked open port can be the difference between a secure network and a full-scale data breach. The LinkedIn post from Hacking Articles highlighting “Pic of the Day” with hashtags like pentesting and cybersecurityawareness serves as a reminder that proactive testing and continuous learning are essential for defenders. This article transforms that daily tip into a hands-on technical guide, covering real-world pentesting commands, detection methods, and hardening techniques for both Linux and Windows environments.

Learning Objectives:

  • Execute and interpret common network scanning and privilege escalation commands used in penetration testing.
  • Implement defensive measures including firewall rules, logging configurations, and endpoint detection responses.
  • Apply cloud hardening and API security checks to prevent unauthorized access in modern infrastructures.

You Should Know:

  1. Network Reconnaissance with Nmap – The Attacker’s First Step

Nmap remains the gold standard for host discovery and port enumeration. Attackers use it to map your attack surface; defenders use it to find weaknesses first.

Step‑by‑step guide explaining what this does and how to use it:
Nmap sends specially crafted packets to target IPs and analyzes responses to determine open ports, running services, and OS fingerprints. A basic scan (nmap -sV -O 192.168.1.0/24) reveals service versions and operating system details. To simulate a stealthier approach, use `nmap -sS -Pn -T4 -f –data-length 200 -D RND:10 ` – this SYN scan avoids full TCP handshakes, skips host discovery, adds fake fragmentation, and decoys traffic. Defenders should run regular internal scans and block unexpected open ports via `iptables -A INPUT -p tcp –dport -j DROP` (Linux) or `New-NetFirewallRule -Direction Inbound -Protocol TCP -LocalPort -Action Block` (PowerShell as Admin).

Commands and configurations to verify:

  • Linux: `sudo nmap -sV -O 192.168.1.1` → outputs open ports, service versions, OS guess.
  • Windows (using Nmap for Windows): `nmap -sS -Pn 10.0.0.5` → SYN scan of a single host.
  • Detection: `sudo tcpdump -i eth0 ‘tcp[bash] & (tcp-syn) != 0’` captures all SYN packets; monitor for unusual source IPs or high-frequency scans.
  1. Privilege Escalation on Linux – Abusing SUID Binaries

Once a low-privilege shell is obtained, attackers hunt for files with the Set‑User‑ID (SUID) bit set. These executables run with the owner’s privileges – often root.

Step‑by‑step guide explaining what this does and how to use it:
Find all SUID binaries with find / -perm -4000 -type f 2>/dev/null. Common exploitable examples include `/usr/bin/pkexec` (CVE‑2021‑4034 – Polkit), /usr/bin/sudo, and custom scripts. If `/usr/bin/python3` has SUID, an attacker can run `python3 -c ‘import os; os.setuid(0); os.system(“/bin/bash”)’` to drop into a root shell. Mitigation: regularly audit SUID files using `find / -perm -4000 -type f -exec ls -la {} \; > suid_report.txt` and remove unnecessary bits with sudo chmod u-s /path/to/binary.

Linux commands and tutorials:

  • List SUID binaries with owner: `find / -perm -4000 -o -perm -2000 -type f -exec ls -la {} \; 2>/dev/null`
    – Monitor SUID creation in real time using auditd: add a rule `-w /bin -p wa -k suid_change` then search `ausearch -k suid_change`
    – Windows alternative: check for service misconfigurations with `sc qc ` or use `accesschk.exe -uwcqv “Authenticated Users” ` (Sysinternals) to find writable services.
  1. Credential Dumping in Windows – Mimikatz in Action

Mimikatz extracts plaintext passwords, hashes, and Kerberos tickets from memory. It’s the go‑to post‑exploitation tool after gaining administrative access.

Step‑by‑step guide explaining what this does and how to use it:
After importing Mimikatz (e.g., via PowerShell or Cobalt Strike), execute `privilege::debug` to enable SeDebugPrivilege, then `sekurlsa::logonpasswords` to dump all active logon credentials. Modern Windows versions require ‘Protected Process Light’ (PPL) bypass. Defenders should enable Credential Guard (Windows Defender Credential Guard) and restrict debug privileges. To detect Mimikatz, look for process access patterns: `Get-WinEvent -LogName Security | Where-Object {$_.Id -eq 4663 -and $_.Message -like “mimikatz”}` or use Sysmon Event ID 10 (ProcessAccess).

Windows commands and hardening:

  • Enable Credential Guard via Group Policy: Computer Configuration → Administrative Templates → System → Device Guard → Turn On Virtualization Based Security → set to “Enabled with UEFI lock”.
  • Remove debug privilege from non‑admin users: secedit /export /cfg secpol.cfg; edit to set SeDebugPrivilege = `; then `secedit /configure /db secedit.sdb /cfg secpol.cfg.
  • Monitor LSASS access attempts: `auditpol /set /subcategory:”Process Creation” /success:enable` and track Event ID 4688 with `lsass.exe` as target.
  1. Cloud Hardening – S3 Bucket Enumeration and IAM Misconfigurations

Misconfigured cloud storage remains the 1 cause of public data leaks. Attackers enumerate buckets via DNS and HTTP requests.

Step‑by‑step guide explaining what this does and how to use it:
Use `aws s3 ls s3://target-bucket –no-sign-request` (if public) or brute‑force bucket names using tools like s3scanner. For IAM, test privilege escalation with `aws iam list-attached-user-policies –user-name ` and check for `”Effect”: “Allow”` with "Resource": "". Defenders: enforce bucket policies that deny public access (aws s3api put-bucket-acl --bucket my-bucket --acl private), enable S3 block public access, and use CloudTrail to log all S3 API calls.

API security and commands:

  • Check for open buckets: `curl -I http://.s3.amazonaws.com` → 200 OK means public listing might be enabled.
  • Automate bucket scanning: `s3enum` tool (Python) – python s3enum.py -b companyname -w wordlist.txt.
  • Remediate overly permissive IAM roles: `aws iam list-roles | jq ‘.Roles[] | select(.AssumeRolePolicyDocument.Statement[].Principal.AWS == “”)’` – then modify policy to restrict principals.
  1. Web Application Pentesting – SQL Injection and XSS Mitigation

Injection flaws and cross‑site scripting still dominate OWASP Top 10. Attackers use `sqlmap` to automate database extraction and craft persistent XSS payloads.

Step‑by‑step guide explaining what this does and how to use it:
For a vulnerable URL `http://example.com/page?id=1`, run `sqlmap -u “http://example.com/page?id=1” –dbs –batchto enumerate databases. For XSS, inject. Defenders must use parameterized queries (e.g.,cursor.execute(“SELECT FROM users WHERE id = ?”, (user_id,))`) and Content Security Policy headers. On Linux with Nginx, add `add_header Content-Security-Policy “default-src ‘self’; script-src ‘self’ https://trusted-cdn.com”;` in server block.

Tutorials and commands:

  • Detect SQLi manually: `’ OR ‘1’=’1` appended to input fields.
  • Use `sqlmap` evasion: `sqlmap -u “target” –tamper=space2comment –level=5 –risk=3`
    – Log all XSS attempts on Apache: `SetEnvIf Referer “.