What is Penetration Testing? Complete Guide to Pen Testing in 2026

What is Penetration Testing?

Penetration testing is a controlled, authorized simulation of a cyberattack conducted by security professionals to identify and exploit vulnerabilities in systems, networks, applications, and physical security controls. Unlike passive security assessments, penetration testing actively attempts to breach defenses using the same tactics, techniques, and procedures (TTPs) employed by real-world threat actors.

The primary objective of penetration testing is to answer a critical question: "Can an attacker compromise our systems, and if so, what damage could they cause?" By discovering weaknesses before malicious actors do, organizations can prioritize remediation efforts and strengthen their security posture.

Key Characteristics of Penetration Testing

• Authorized and Controlled: All testing is performed with explicit written permission and defined boundaries
• Simulates Real Attacks: Uses actual attacker methodologies and tools
• Goes Beyond Detection: Attempts to exploit vulnerabilities to assess real-world impact
• Manual and Automated: Combines human expertise with sophisticated tools
• Risk-Focused: Prioritizes findings based on business impact and exploitability
• Documented and Actionable: Provides detailed reports with remediation guidance

Why Penetration Testing Matters

In 2023, global cybercrime costs reached an estimated $8 trillion, with projections indicating continued growth. Penetration testing serves as a proactive defense mechanism that provides tangible benefits across multiple dimensions:

1. Identify Vulnerabilities Before Attackers Do

Penetration testing uncovers security weaknesses that automated tools often miss. According to Verizon's 2023 Data Breach Investigations Report, 74% of breaches involve the human element, social engineering, errors, or misuse, vulnerabilities that only manual testing effectively identifies.

2. Validate Security Controls

Organizations invest heavily in security technologies like firewalls, intrusion detection systems, and endpoint protection. Penetration testing validates whether these controls function as intended when faced with real-world attack scenarios.

3. Regulatory Compliance Requirements

Many compliance frameworks explicitly require or strongly recommend regular penetration testing:

• PCI DSS: Mandates annual external and internal penetration testing
• HIPAA: Requires regular security assessments and testing
• GDPR: Emphasizes security testing as part of data protection measures
• SOC 2: Often includes penetration testing in security control evaluations
• ISO 27001: Recommends regular technical vulnerability assessments

4. Prevent Financial Losses

The average cost of a data breach in 2023 was $4.45 million. A comprehensive penetration test typically costs between $15,000 and $40,000, representing less than 1% of the potential breach cost. Organizations that conduct regular testing experience 51% lower breach costs compared to those that don't, according to IBM Security research.

5. Protect Reputation and Customer Trust

Public data breaches damage brand reputation and erode customer confidence. 65% of consumers lose trust in organizations following a breach, and 27% stop doing business with them entirely. Proactive security testing demonstrates due diligence and commitment to protecting customer data.

6. Prioritize Security Investments

Penetration testing provides data-driven insights for security budget allocation. By understanding which vulnerabilities pose the greatest risk, organizations can prioritize remediation efforts and technology investments for maximum impact.

Types of Penetration Testing

Penetration testing encompasses various specialized assessments, each targeting different aspects of an organization's security infrastructure:

1. Network Penetration Testing

Network penetration testing evaluates the security of network infrastructure, including routers, switches, firewalls, and network segmentation. This testing identifies vulnerabilities in both external (internet-facing) and internal network environments.

External Network Testing: Simulates attacks from outside the organization, testing perimeter defenses and internet-facing assets.

Internal Network Testing: Assumes an attacker has gained initial access or simulates insider threats, evaluating lateral movement capabilities and internal security controls.

Common Focus Areas:

• Firewall configuration and rule effectiveness
• Network segmentation and VLAN security
• Wireless network security (WiFi, Bluetooth)
• VPN implementations and remote access
• Network protocol vulnerabilities
• DNS security and DNSSEC

2. Web Application Penetration Testing

Web application testing focuses on identifying vulnerabilities in web-based applications, APIs, and their underlying infrastructure. With 43% of data breaches targeting web applications, this testing type is critical for organizations with online presence.

Testing Coverage:

• OWASP Top 10 vulnerabilities (SQL injection, XSS, CSRF, etc.)
• Authentication and session management flaws
• Business logic vulnerabilities
• API security and REST/GraphQL endpoints
• File upload vulnerabilities
• Server-side request forgery (SSRF)
• Insecure deserialization

3. Mobile Application Penetration Testing

Mobile app testing assesses security for iOS and Android applications, examining client-side vulnerabilities, insecure data storage, and backend API security.

Key Assessment Areas:

• Insecure data storage on devices
• Weak cryptography implementations
• Insecure communication channels
• Authentication and authorization bypasses
• Code tampering and reverse engineering risks
• Platform-specific vulnerabilities (Android/iOS)

4. Social Engineering Testing

Social engineering assessments evaluate human vulnerabilities through simulated phishing campaigns, pretexting, baiting, and other psychological manipulation techniques. Since 82% of breaches involve a human element, this testing provides critical insights into security awareness effectiveness.

Common Techniques:

• Phishing email campaigns
• Vishing (voice phishing) attempts
• SMS phishing (smishing)
• Physical social engineering
• USB drop attacks
• Impersonation attempts

5. Physical Penetration Testing

Physical testing evaluates the effectiveness of physical security controls by attempting unauthorized access to facilities, server rooms, and restricted areas.

Testing Objectives:

• Badge access system bypasses
• Lock picking and physical barriers
• Security guard effectiveness
• Tailgating and piggybacking opportunities
• CCTV blind spots and surveillance gaps
• Sensitive document handling

6. Cloud Penetration Testing

Cloud testing assesses security configurations and vulnerabilities in cloud environments (AWS, Azure, GCP), including misconfigurations, IAM weaknesses, and container security.

Focus Areas:

• Cloud storage bucket permissions (S3, Blob, etc.)
• Identity and Access Management (IAM) misconfigurations
• Serverless function security (Lambda, Azure Functions)
• Container and Kubernetes security
• Cloud API security
• Multi-tenant isolation issues

Penetration Testing Methodologies

Professional penetration testers follow established methodologies that provide structured, repeatable, and comprehensive testing processes. These frameworks ensure consistency, thoroughness, and alignment with industry standards.

OWASP Testing Guide

The Open Web Application Security Project (OWASP) provides comprehensive testing methodologies specifically for web applications. The OWASP Testing Guide covers:

• Information gathering and reconnaissance
• Configuration and deployment management testing
• Identity management testing
• Authentication and session management testing
• Authorization testing
• Business logic testing
• Data validation testing
• Error handling and logging

PTES (Penetration Testing Execution Standard)

PTES provides a standard methodology covering all aspects of penetration testing execution:

• Pre-engagement Interactions: Scope definition and rules of engagement
• Intelligence Gathering: Information collection about the target
• Threat Modeling: Identifying potential attack vectors
• Vulnerability Analysis: Discovering weaknesses
• Exploitation: Attempting to compromise systems
• Post Exploitation: Assessing impact and persistence
• Reporting: Documenting findings and recommendations

NIST SP 800-115

The National Institute of Standards and Technology (NIST) Special Publication 800-115 provides guidance on technical security testing and assessment, including:

• Review techniques (documentation, logs, rule sets)
• Target identification and analysis techniques
• Target vulnerability validation techniques
• Security assessment planning
• Assessment execution
• Post-assessment activities

OSSTMM (Open Source Security Testing Methodology Manual)

OSSTMM focuses on scientific methodology for security testing across multiple channels:

• Human security testing
• Physical security testing
• Wireless security testing
• Telecommunications security testing
• Data networks security testing

MITRE ATT&CK Framework

The MITRE ATT&CK (Adversarial Tactics, Techniques, and Common Knowledge) framework provides a knowledge base of real-world adversary behaviors. Penetration testers use ATT&CK to:

• Model threat actor TTPs (Tactics, Techniques, and Procedures)
• Prioritize testing based on relevant threat actors
• Map findings to known attack patterns
• Communicate results using industry-standard terminology

The Five Phases of Penetration Testing

Regardless of methodology, most penetration tests follow five core phases:

Phase 1: Reconnaissance and Information Gathering

The reconnaissance phase involves collecting information about the target environment. This passive and active information gathering establishes the foundation for subsequent testing phases.

Passive Reconnaissance: Gathering publicly available information without directly interacting with target systems:

• WHOIS database queries
• DNS record enumeration
• Search engine discovery
• Social media intelligence gathering
• Public financial filings and documents
• Job postings revealing technology stacks
• Data breach repositories

Active Reconnaissance: Directly probing target systems for information:

• Port scanning and service detection
• Operating system fingerprinting
• Network mapping and topology discovery
• Web application fingerprinting
• Email address harvesting
• Subdomain enumeration

Phase 2: Scanning and Vulnerability Assessment

The scanning phase identifies potential vulnerabilities using both automated tools and manual techniques:

Network Scanning:

• Port scanning (TCP, UDP)
• Service version detection
• Network vulnerability scanning
• SSL/TLS configuration testing
• Network protocol analysis

Application Scanning:

• Web application vulnerability scanning
• Database security scanning
• API endpoint testing
• Authentication mechanism analysis
• Input validation testing

Phase 3: Exploitation

The exploitation phase attempts to leverage identified vulnerabilities to gain unauthorized access or demonstrate security impact. This phase requires careful consideration of potential system damage and business disruption.

Common Exploitation Techniques:

• Exploiting unpatched software vulnerabilities
• Brute force and password cracking attacks
• SQL injection and command injection
• Cross-site scripting (XSS) exploitation
• Buffer overflow exploits
• Privilege escalation attempts
• Authentication bypass
• Session hijacking

Exploitation Considerations:

• Risk of system crashes or service disruption
• Data integrity concerns
• Production vs. testing environment differences
• Timing and business impact windows
• Escalation procedures for critical findings

Phase 4: Post-Exploitation

After successful exploitation, testers assess the extent of access gained and potential business impact:

Post-Exploitation Activities:

• Privilege escalation to higher-level accounts
• Lateral movement across the network
• Data exfiltration demonstrations
• Persistence mechanism establishment
• Additional system compromise
• Covering tracks (simulating attacker behavior)
• Pivoting to other network segments

This phase answers critical questions:

• What sensitive data can be accessed?
• How far can an attacker move within the network?
• What level of system control can be achieved?
• Can administrative access be obtained?
• What business-critical systems are at risk?

Phase 5: Reporting and Remediation

The final phase involves documenting findings, assessing risks, and providing actionable remediation guidance:

Report Components:

• Executive Summary: High-level overview for business stakeholders
• Methodology: Testing approach and scope
• Findings Summary: Overview of discovered vulnerabilities
• Technical Details: Detailed vulnerability descriptions
• Risk Ratings: CVSS scores and business impact assessments
• Proof of Concept: Evidence demonstrating exploitation
• Remediation Recommendations: Specific fix guidance
• Strategic Recommendations: Long-term security improvements

Common Penetration Testing Techniques

Penetration testers employ diverse techniques to identify and exploit vulnerabilities:

Network-Based Techniques

Man-in-the-Middle (MitM) Attacks: Intercepting communications between two parties to eavesdrop or manipulate data. Techniques include ARP spoofing, DNS poisoning, and SSL stripping.

Packet Sniffing: Capturing and analyzing network traffic to identify sensitive information transmitted in clear text, weak encryption, or authentication credentials.

Port Scanning: Systematically probing target systems to identify open ports and running services, revealing potential attack vectors.

Denial of Service (DoS): Testing system resilience against resource exhaustion attacks (typically performed with extreme caution or not at all in production).

Web Application Techniques

SQL Injection: Injecting malicious SQL code into application inputs to manipulate database queries, potentially extracting, modifying, or deleting data.

Cross-Site Scripting (XSS): Injecting malicious scripts into web pages viewed by other users, enabling session hijacking, phishing, or defacement.

Cross-Site Request Forgery (CSRF): Tricking authenticated users into executing unwanted actions on web applications where they're authenticated.

Server-Side Request Forgery (SSRF): Manipulating applications to make requests to internal resources, potentially accessing restricted systems or data.

XML External Entity (XXE) Injection: Exploiting vulnerable XML processors to access local files, perform SSRF attacks, or cause denial of service.

Authentication and Access Control Techniques

Brute Force Attacks: Systematically attempting numerous password combinations to gain unauthorized access.

Dictionary Attacks: Using lists of common passwords and variations to compromise accounts more efficiently than pure brute force.

Credential Stuffing: Using previously breached username/password combinations from other services, exploiting password reuse.

Pass-the-Hash: Using captured password hashes to authenticate to systems without knowing the actual plaintext password.

Privilege Escalation: Exploiting vulnerabilities or misconfigurations to gain elevated access rights beyond initially compromised accounts.

Social Engineering Techniques

Phishing: Crafting deceptive emails to trick recipients into revealing credentials, downloading malware, or transferring funds.

Spear Phishing: Targeted phishing attacks customized for specific individuals or organizations, often incorporating personal information for credibility.

Pretexting: Creating fabricated scenarios to manipulate targets into divulging confidential information.

Baiting: Offering something enticing (USB drives, free software) infected with malware.

Wireless Network Techniques

Evil Twin Attacks: Creating rogue wireless access points that mimic legitimate networks to intercept traffic.

WPA/WPA2 Cracking: Capturing wireless handshakes and using offline attacks to recover passwords.

Rogue Access Point Detection: Identifying unauthorized wireless access points that bypass security controls.

Essential Penetration Testing Tools

Professional penetration testers leverage specialized tools across different testing phases:

Reconnaissance Tools

• Nmap: Network discovery and port scanning
• Maltego: Visual intelligence gathering and link analysis
• theHarvester: Email, subdomain, and information harvesting
• Recon-ng: Web reconnaissance framework
• Shodan: Internet-connected device search engine

Vulnerability Scanning Tools

• Nessus: Comprehensive vulnerability scanner
• OpenVAS: Open-source vulnerability assessment system
• Qualys: Cloud-based vulnerability management
• Burp Suite: Web application security testing
• OWASP ZAP: Open-source web app scanner

Exploitation Frameworks

• Metasploit: Industry-standard penetration testing framework
• Cobalt Strike: Advanced adversary simulation software
• Empire: Post-exploitation framework
• BeEF: Browser exploitation framework

Password Cracking Tools

• John the Ripper: Password cracking utility
• Hashcat: Advanced password recovery tool
• Hydra: Network authentication cracker
• Medusa: Parallel brute-force attack tool

Network Analysis Tools

• Wireshark: Network protocol analyzer
• tcpdump: Command-line packet analyzer
• Responder: LLMNR, NBT-NS, and MDNS poisoner
• Bettercap: Swiss Army knife for network attacks

Web Application Testing Tools

• SQLMap: Automated SQL injection tool
• Nikto: Web server scanner
• Dirb/Dirbuster: Web content scanner
• WPScan: WordPress vulnerability scanner

Social Engineering Tools

• Social-Engineer Toolkit (SET): Social engineering attack framework
• Gophish: Phishing campaign framework
• King Phisher: Phishing campaign toolkit

Black Box vs. White Box vs. Grey Box Testing

Penetration tests can be conducted with varying levels of knowledge about the target environment, each offering unique advantages:

Black Box Testing

Black box testing simulates an external attacker with no prior knowledge of the target environment. Testers begin with only publicly available information.

Advantages:

• Most closely simulates real-world external attacks
• Tests external defenses from an adversarial perspective
• Identifies vulnerabilities discoverable through reconnaissance
• Validates public-facing security posture

Disadvantages:

• More time-consuming reconnaissance phase
• May miss internal vulnerabilities
• Limited coverage given time constraints
• Higher costs due to extended timelines

Best For: Organizations wanting to understand external threat exposure and validate perimeter defenses.

White Box Testing

White box testing (also called clear box or glass box) provides testers with complete knowledge of the target environment, including network diagrams, source code, credentials, and system documentation.

Advantages:

• Maximum vulnerability coverage
• More efficient use of testing time
• Comprehensive assessment of internal security
• Identifies complex logic flaws
• Better value for testing budget

Disadvantages:

• Doesn't simulate realistic external attacks
• May identify vulnerabilities unreachable by real attackers
• Requires significant client preparation and information sharing

Best For: Organizations seeking comprehensive security assessments and maximum vulnerability discovery, particularly for compliance requirements.

Grey Box Testing

Grey box testing provides partial knowledge, typically simulating a compromised insider or an attacker with limited access. This might include user-level credentials or network access.

Advantages:

• Balances realism with efficiency
• Simulates common attack scenarios (compromised accounts)
• More thorough than black box, faster than white box
• Evaluates insider threat risks

Disadvantages:

• May not fully represent external or internal perspectives
• Knowledge level must be carefully defined

Best For: Organizations wanting realistic attack simulations with reasonable time and budget constraints, or those specifically concerned about insider threats.

Penetration Testing vs. Vulnerability Scanning

Organizations often confuse penetration testing with vulnerability scanning. While related, these are distinct security assessment approaches:

Vulnerability Scanning

Vulnerability scanning is an automated process that identifies potential security weaknesses by comparing system configurations against known vulnerability databases.

Characteristics:

• Primarily automated tool-based
• Identifies known vulnerabilities
• Provides broad coverage quickly
• Generates large volumes of findings
• Lower cost and faster execution
• Can be performed frequently (weekly/monthly)

Penetration Testing

Penetration testing involves skilled security professionals manually exploiting vulnerabilities to assess real-world impact.

Characteristics:

• Manual testing with human expertise
• Validates vulnerabilities through exploitation
• Identifies complex and logical vulnerabilities
• Assesses business impact and risk
• Higher cost and longer duration
• Typically performed annually or after major changes

Key Differences

Complementary Approaches

Rather than choosing between vulnerability scanning and penetration testing, organizations should implement both as complementary security measures:

• Regular Vulnerability Scanning: Continuous monitoring for known vulnerabilities
• Annual Penetration Testing: In-depth assessment of real-world exploitability
• Vulnerability Validation: Using pen testing to confirm critical scan findings
• Remediation Prioritization: Focusing fixes on validated exploitable vulnerabilities

Compliance and Regulatory Requirements

Many regulatory frameworks and industry standards require or strongly recommend regular penetration testing:

PCI DSS (Payment Card Industry Data Security Standard)

Requirement 11.3: Mandates external and internal penetration testing at least annually and after significant infrastructure or application changes.

Specific Requirements:

• External penetration testing annually
• Internal penetration testing annually
• Testing after significant changes
• Testing by qualified internal resources or external third parties
• Remediation of high-risk vulnerabilities
• Re-testing after remediation

HIPAA (Health Insurance Portability and Accountability Act)

HIPAA Security Rule requires covered entities to conduct regular security assessments, including penetration testing as part of risk analysis requirements.

Requirements:

• Regular technical and non-technical evaluations
• Testing security controls effectiveness
• Identifying vulnerabilities and security gaps
• Documenting testing procedures and results

GDPR (General Data Protection Regulation)

While not explicitly mandating penetration testing, GDPR requires organizations to implement appropriate technical measures to ensure data security, which industry best practices interpret to include regular security testing.

Article 32 Requirements:

• Regular testing and assessment of security measures
• Ability to ensure ongoing confidentiality and integrity
• Demonstrating appropriate security controls

SOC 2 (Service Organization Control 2)

SOC 2 audits often include penetration testing as evidence of effective security controls, particularly for the Security and Availability principles.

Common Requirements:

• Annual penetration testing
• Testing scope covering in-scope systems
• Documentation of findings and remediation
• Independent testing by qualified assessors

ISO 27001

ISO 27001 Annex A.12.6 recommends technical vulnerability management, including regular penetration testing and vulnerability assessments.

Best Practices:

• Regular security testing of systems
• Timely response to vulnerability disclosures
• Risk-based approach to testing frequency
• Documentation of testing methodology and results

FFIEC (Federal Financial Institutions Examination Council)

FFIEC guidance requires financial institutions to conduct regular independent penetration testing covering networks, systems, and applications.

Requirements:

• Scope includes all critical systems
• Testing by independent third parties
• Annual testing minimum
• Testing after significant changes

Choosing a Penetration Testing Provider

Selecting the right penetration testing provider is critical for obtaining valuable security insights and maximizing your testing investment:

Key Selection Criteria

1. Certifications and Qualifications

Verify that testers hold relevant certifications demonstrating technical competence:

• OSCP (Offensive Security Certified Professional): Hands-on penetration testing certification
• CEH (Certified Ethical Hacker): Foundational ethical hacking knowledge
• GPEN (GIAC Penetration Tester): Technical penetration testing skills
• CREST: International penetration testing certifications
• PNPT (Practical Network Penetration Tester): Practical pentesting skills

2. Industry Experience and Expertise

Look for providers with experience in your specific industry:

• Understanding of industry-specific threats
• Knowledge of compliance requirements
• Experience with similar technology stacks
• Relevant case studies and references

3. Methodology and Standards

Ensure providers follow recognized testing methodologies:

• PTES, OWASP, or NIST-based approaches
• Clear scope definition processes
• Structured testing phases
• Quality assurance procedures
• Risk rating methodologies (CVSS, etc.)

4. Reporting Quality

Request sample reports to evaluate:

• Clarity and comprehensiveness
• Executive and technical audience consideration
• Actionable remediation guidance
• Risk prioritization
• Evidence and proof-of-concept quality

5. Communication and Support

Assess communication practices:

• Project management and coordination
• Escalation procedures for critical findings
• Availability during testing
• Post-testing support and re-testing
• Remediation validation services

6. Insurance and Legal Protections

Verify adequate protections:

• Professional liability insurance
• Cyber liability coverage
• Clear rules of engagement
• Non-disclosure agreements
• Liability limitations and indemnification

Red Flags to Avoid

• Overly aggressive sales tactics
• Unrealistically low pricing
• Lack of formal methodology
• Unwillingness to provide references
• No formal reporting structure
• Inadequate insurance coverage
• Offshore-only testing teams (for sensitive environments)

Questions to Ask Potential Providers

1. What certifications do your testers hold?
2. How many years of experience do your testers have?
3. What methodology do you follow?
4. Can you provide references from similar organizations?
5. What does your typical report include?
6. How do you handle critical findings discovered during testing?
7. Do you offer remediation validation and re-testing?
8. What insurance coverage do you maintain?
9. How do you ensure data confidentiality?
10. What is your approach to scope changes during testing?

Best Practices for Effective Pen Testing

Maximize the value of penetration testing by following these best practices:

Before Testing

1. Define Clear Objectives and Scope

• Identify specific systems, applications, or networks to test
• Determine testing approach (black/white/grey box)
• Establish business objectives and risk concerns
• Define testing constraints and limitations
• Identify off-limits systems or actions

2. Obtain Proper Authorization

• Secure written permission from system owners
• Document rules of engagement
• Notify relevant stakeholders
• Establish emergency contact procedures
• Define testing windows and timing

3. Prepare the Environment

• Backup critical systems before testing
• Document baseline configurations
• Ensure monitoring systems are operational
• Coordinate with IT and security teams
• Prepare for potential service disruptions

4. Choose the Right Time

• Avoid peak business periods when possible
• Consider maintenance windows for disruptive tests
• Schedule around major projects or changes
• Allow sufficient time for thorough testing

During Testing

1. Maintain Communication

• Establish regular check-ins with testing team
• Report critical findings immediately
• Coordinate timing of high-risk activities
• Document any scope adjustments
• Address issues or concerns promptly

2. Monitor for Impact

• Watch for performance degradation
• Monitor system availability
• Track unusual activity in logs
• Be prepared to pause or stop testing if needed

3. Document Everything

• Maintain detailed testing logs
• Capture screenshots and evidence
• Document all findings in real-time
• Record remediation recommendations

After Testing

1. Review Findings Thoroughly

• Schedule a findings presentation/debrief
• Understand each vulnerability and its impact
• Ask questions about unclear findings
• Discuss remediation priorities
• Review proof-of-concept demonstrations

2. Prioritize Remediation

• Focus on high-risk, easily exploitable vulnerabilities first
• Consider business impact alongside technical severity
• Create realistic remediation timelines
• Assign clear ownership for fixes
• Track remediation progress

3. Validate Fixes

• Test that remediation efforts are effective
• Verify fixes don't introduce new vulnerabilities
• Request re-testing of critical findings
• Document verification results

4. Learn and Improve

• Conduct internal lessons learned sessions
• Update security policies and procedures
• Enhance security awareness training
• Improve change management processes
• Strengthen security architecture

5. Plan Future Testing

• Schedule next testing cycle
• Expand scope to cover new systems
• Consider different testing approaches
• Budget for ongoing security assessments

Most Common Vulnerabilities Discovered

Penetration tests consistently uncover certain classes of vulnerabilities across organizations:

1. Weak or Default Credentials

Prevalence: Found in 60%+ of penetration tests

Default or weak passwords remain one of the most common findings, enabling attackers to gain unauthorized access to systems, applications, and network devices.

Common Examples:

• Default admin credentials on network equipment
• Weak password policies allowing simple passwords
• Shared credentials across multiple systems
• Service accounts with unchanging passwords
• Hardcoded credentials in applications

2. Missing Security Patches

Prevalence: Found in 55%+ of penetration tests

Unpatched systems with known vulnerabilities provide easy exploitation opportunities for attackers.

Common Gaps:

• Operating system patches not applied
• Outdated third-party software
• End-of-life systems without support
• Delayed patch deployment processes
• Legacy applications preventing updates

3. Misconfigured Security Settings

Prevalence: Found in 50%+ of penetration tests

Improper security configurations expose systems to unnecessary risks.

Common Misconfigurations:

• Overly permissive firewall rules
• Unnecessary services running
• Insecure SSL/TLS configurations
• Publicly accessible administrative interfaces
• Improper file and directory permissions
• Cloud storage bucket misconfigurations

4. Insufficient Access Controls

Prevalence: Found in 45%+ of penetration tests

Inadequate access restrictions allow unauthorized users to access sensitive data or functionality.

Common Issues:

• Broken authorization checks
• Privilege escalation opportunities
• Inadequate role-based access controls
• Direct object reference vulnerabilities
• Missing function-level access controls

5. SQL Injection

Prevalence: Found in 35%+ of web application tests

Despite being a well-known vulnerability, SQL injection continues to affect web applications, potentially exposing entire databases.

Impact:

• Complete database compromise
• Data theft or modification
• Authentication bypass
• Remote code execution in some cases

6. Cross-Site Scripting (XSS)

Prevalence: Found in 40%+ of web application tests

XSS vulnerabilities allow attackers to inject malicious scripts into trusted websites.

Types and Impact:

• Stored XSS (persistent attacks)
• Reflected XSS (immediate execution)
• DOM-based XSS (client-side vulnerabilities)
• Session hijacking and credential theft

7. Insecure Communication

Prevalence: Found in 40%+ of penetration tests

Unencrypted or weakly encrypted communications expose sensitive data in transit.

Common Problems:

• Unencrypted HTTP instead of HTTPS
• Weak SSL/TLS cipher suites
• Lack of certificate validation
• Cleartext protocols (FTP, Telnet, etc.)
• Inadequate VPN configurations

8. Information Disclosure

Prevalence: Found in 50%+ of penetration tests

Unnecessary information leakage aids attackers in reconnaissance and exploitation.

Common Leaks:

• Verbose error messages revealing system details
• Directory listings enabled
• Exposed backup files and source code
• Detailed banner information
• Comments in HTML source containing sensitive data

9. Session Management Vulnerabilities

Prevalence: Found in 30%+ of web application tests

Weak session handling allows attackers to hijack user sessions.

Common Issues:

• Predictable session tokens
• Session fixation vulnerabilities
• Missing secure and HTTPOnly flags on cookies
• Inadequate session timeout settings
• Session tokens exposed in URLs

10. Social Engineering Susceptibility

Prevalence: Successful in 15-20% of simulated phishing campaigns

Human vulnerabilities remain a significant attack vector.

Common Successes:

• Phishing email click-through rates
• Credential disclosure through pretexting
• Physical access gained through tailgating
• Malicious USB device insertions
• Sensitive information disclosure over phone

Understanding Penetration Test Reports

A comprehensive penetration test report serves as the primary deliverable, providing actionable intelligence for improving security posture:

Executive Summary

The executive summary provides a high-level overview for non-technical stakeholders:

• Overall Risk Assessment: Summary of security posture
• Key Findings: Most critical vulnerabilities discovered
• Business Impact: Potential consequences of exploitation
• Prioritized Recommendations: Top remediation actions
• Comparison to Previous Tests: Progress and trends

Technical Details Section

Technical sections provide in-depth information for security and IT teams:

Methodology and Scope

• Testing approach and frameworks used
• Systems and applications in scope
• Testing limitations and constraints
• Testing timeline and duration

Vulnerability Findings

Each vulnerability should include:

• Title: Clear, descriptive name
• Severity Rating: CVSS score and risk level (Critical/High/Medium/Low)
• Description: Detailed explanation of the vulnerability
• Location: Affected systems, applications, or components
• Impact: Potential business and technical consequences
• Proof of Concept: Evidence demonstrating exploitability
• Remediation: Specific steps to fix the vulnerability
• References: CVE numbers, vendor advisories, and resources

Attack Narratives

Detailed descriptions of successful attack chains:

• Initial access methods
• Lateral movement techniques
• Privilege escalation paths
• Data access achievements
• Overall impact demonstration

Remediation Recommendations

Actionable guidance prioritized by risk and effort:

Immediate Actions (Critical/High Risk)

• Vulnerabilities requiring immediate attention
• Quick wins for significant risk reduction
• Emergency remediation steps

Short-Term Actions (1-3 months)

• Important fixes requiring planning
• Moderate-risk vulnerabilities
• Security control enhancements

Long-Term Strategic Improvements

• Architecture and design improvements
• Policy and procedure updates
• Security program enhancements
• Technology upgrades and replacements

Appendices

Supporting information and detailed technical data:

• Tools and Techniques: Methodologies employed
• Raw Scan Data: Detailed technical output
• Screenshots: Visual evidence of findings
• Code Samples: Exploit code or scripts used
• Network Diagrams: Visual representation of testing scope
• Glossary: Technical term definitions

Report Quality Indicators

A high-quality penetration test report should:

• Be clear and comprehensible to both technical and business audiences
• Provide specific, actionable remediation guidance
• Include proof-of-concept for significant findings
• Prioritize findings based on risk and business impact
• Contain sufficient detail for reproduction and verification
• Follow a consistent, professional format
• Be delivered securely with appropriate confidentiality controls

Penetration Testing Costs and Pricing

Penetration testing costs vary significantly based on scope, complexity, and duration. Understanding pricing models helps organizations budget appropriately:

Pricing Models

1. Fixed-Scope Pricing

Most common for clearly defined testing engagements:

• Predictable costs for budgeting
• Requires well-defined scope
• Changes may incur additional fees
• Typical range: $5,000 - $100,000+

2. Time and Materials

Billing based on actual hours worked:

• Flexible for evolving requirements
• Hourly rates typically $150 - $400+
• Less predictable total costs
• Good for exploratory or undefined scopes

3. Retainer-Based Pricing

Ongoing security testing relationships:

• Monthly or annual retainer fees
• Includes multiple testing cycles
• Often includes remediation re-testing
• Provides consistent security assessment

Cost Factors

Scope and Complexity:

• Number of systems, applications, or networks
• Technology stack complexity
• Custom application vs. commercial software
• Network size and segmentation

Testing Duration:

• Small assessments: 40-80 hours ($6,000-$15,000)
• Medium assessments: 80-160 hours ($15,000-$40,000)
• Large assessments: 160-320+ hours ($40,000-$100,000+)

Testing Type:

• Black box testing (highest cost)
• Grey box testing (moderate cost)
• White box testing (potentially lower cost due to efficiency)

Tester Expertise:

• Junior testers: $100-$150/hour
• Mid-level testers: $150-$250/hour
• Senior testers: $250-$400+/hour
• Specialized expertise (mobile, IoT, ICS): Premium pricing

Typical Cost Ranges by Testing Type

Additional Costs to Consider

• Re-testing: $2,000 - $10,000 to validate fixes
• Remediation Support: $150 - $300/hour for guidance
• Emergency/Expedited Testing: 25-50% premium
• After-Hours Testing: 10-25% premium
• Travel Expenses: For physical testing or on-site requirements

Maximizing Testing Value

Get the most from your penetration testing investment:

• Prepare Thoroughly: Well-defined scopes reduce wasted time
• Provide White Box Access When Appropriate: Increases coverage efficiency
• Schedule During Optimal Windows: Avoid rushed or incomplete assessments
• Plan for Remediation: Budget includes fixing identified issues
• Leverage Findings for Training: Use results to improve security awareness
• Establish Long-Term Relationships: Retainers often provide better value

Frequently Asked Questions