Penetration Testing &
Vulnerability Assessment
Identify and exploit security weaknesses before attackers do. Our certified ethical hackers simulate real-world attacks against your infrastructure, applications, and people — delivering actionable findings that strengthen your defenses and satisfy compliance requirements.
What Is Penetration Testing?
Penetration testing — often called "pen testing" or "ethical hacking" — is a controlled, authorized simulation of a cyberattack against your systems. Unlike automated vulnerability scanning, penetration testing uses the same tools, techniques, and methodologies employed by real-world threat actors to identify exploitable weaknesses in your environment.
The goal isn't just to find vulnerabilities — it's to demonstrate real business impact. Our testers chain together seemingly minor issues to show how an attacker could gain unauthorized access, exfiltrate data, or disrupt operations.
Automated scans find known CVEs. Pen testing goes further — exploiting weaknesses, testing business logic, and chaining findings to demonstrate real attack paths scanners miss.
Not all vulnerabilities are equal. We rate findings by actual exploitability and business impact — helping you focus remediation on issues that matter most.
Required by PCI DSS, HIPAA, SOC 2, ISO 27001, and more. Our reports satisfy auditors while giving your technical team actionable remediation guidance.
Comprehensive Testing Services
From network infrastructure to human vulnerabilities, we test every layer of your security stack using industry-standard methodologies and real-world attack techniques.
External Network Penetration Testing
We attack your internet-facing infrastructure the way a remote attacker would — probing firewalls, VPNs, mail servers, DNS, and web servers for exploitable weaknesses.
- ✓ Perimeter firewall & IDS/IPS testing
- ✓ VPN gateway exploitation
- ✓ Public-facing service enumeration
- ✓ DNS & mail server hardening review
- ✓ SSL/TLS configuration analysis
- ✓ Remote access vulnerability testing
Internal Network Penetration Testing
Simulating an insider threat or compromised endpoint, we move laterally through your network — escalating privileges and testing segmentation controls.
- ✓ Active Directory attack simulation
- ✓ Privilege escalation testing
- ✓ Lateral movement & pivoting
- ✓ Network segmentation validation
- ✓ Credential harvesting & relay attacks
- ✓ Sensitive data access testing
Web Application Penetration Testing
We go beyond OWASP Top 10 scanning to manually test authentication flows, business logic, session management, and data handling for exploitable flaws.
- ✓ OWASP Top 10 vulnerability testing
- ✓ Authentication & session management
- ✓ SQL injection & XSS exploitation
- ✓ Business logic flaw testing
- ✓ File upload & input validation
- ✓ API endpoint security testing
API Security Testing
APIs power modern apps but often lack security controls. We test REST, GraphQL, and SOAP APIs for auth bypasses, injection flaws, rate limiting, and data exposure.
- ✓ REST & GraphQL endpoint testing
- ✓ Authentication & token validation
- ✓ Authorization & access control bypass
- ✓ Rate limiting & abuse testing
- ✓ Data exposure & serialization flaws
- ✓ API versioning & deprecation risks
Wireless Network Testing
Wireless networks extend your attack surface beyond physical boundaries. We test Wi-Fi for rogue access points, weak encryption, and infiltration opportunities.
- ✓ WPA2/WPA3 security assessment
- ✓ Rogue access point detection
- ✓ Evil twin attack simulation
- ✓ Client isolation & segmentation
- ✓ Guest network security review
- ✓ Bluetooth & IoT device scanning
Social Engineering & Phishing
We design realistic phishing campaigns, vishing calls, and pretexting scenarios to measure human vulnerability and improve security awareness.
- ✓ Targeted spear-phishing campaigns
- ✓ Vishing (voice phishing) simulations
- ✓ Pretexting & impersonation testing
- ✓ USB drop & physical access testing
- ✓ Security awareness benchmarking
- ✓ Employee response rate analysis
Real-World Scenarios We Test For
Every penetration test is tailored to your industry, compliance requirements, and threat landscape.
PCI DSS Requirement 11.3
Annual penetration testing of cardholder data environments, segmentation controls, and payment processing systems to maintain PCI compliance.
SOC 2 Type II Audit Preparation
Demonstrate security control effectiveness with documented penetration testing results that satisfy SOC 2 trust service criteria.
HIPAA Security Risk Assessment
Test technical safeguards protecting ePHI including access controls, encryption, audit logging, and network segmentation.
Banking & Fintech Security
Assess online banking platforms, payment gateways, and financial APIs for vulnerabilities that could lead to fraud or data breaches.
Pre-Acquisition Due Diligence
Evaluate acquisition target security posture to identify hidden risks, technical debt, and potential liabilities before closing.
Post-Breach Validation
After a security incident, verify remediation efforts are effective and the same attack vectors can no longer be exploited.
Our 5-Step Testing Methodology
Aligned with PTES and OWASP standards for thorough, consistent results on every engagement.
Scoping & Rules of Engagement
Define scope, objectives, testing windows, communication protocols, critical systems, and how critical findings get escalated in real time.
Reconnaissance & Discovery
Gather intelligence using passive and active techniques — mapping topology, identifying services, fingerprinting tech, and discovering attack vectors.
Exploitation & Attack Simulation
Exploit vulnerabilities, chain findings, escalate privileges, move laterally, and demonstrate maximum business impact — documenting every step.
Analysis & Reporting
Comprehensive report with executive summary, detailed technical findings, proof-of-concept evidence, CVSS scores, and prioritized remediation guidance.
Remediation Support & Retesting
We provide remediation guidance and free retesting of critical and high-severity vulnerabilities to verify your fixes are effective.
Why Choose ACS for Penetration Testing
Deep technical expertise with a business-first approach — findings that matter to your security team and your boardroom.
Certified Expert Testers
OSCP, OSCE, GPEN, GWAPT, and CEH certified. Continuous training and research to stay ahead of evolving attack techniques.
Business-Impact Reporting
Beyond technical CVE lists — we translate findings into business risk language with executive summaries for leadership.
Manual Testing Focus
Every engagement includes extensive manual testing. We find business logic flaws and chained vulnerabilities that scanners miss.
Frequently Asked Questions
Common questions about our penetration testing services and what to expect.
Duration depends on scope. A focused external test takes 1-2 weeks; comprehensive multi-vector assessments take 3-4 weeks. We provide a detailed timeline during scoping based on your environment.
We minimize disruption by identifying critical systems during scoping and agreeing on testing windows. DoS testing requires explicit approval. Our testers probe for vulnerabilities without causing outages.
Black box simulates an external attacker with no knowledge. Gray box provides credentials or diagrams to simulate insider threats. White box gives full source code access for maximum depth. We recommend the approach matching your threat model.
Annually at minimum per most compliance frameworks. We recommend testing after major infrastructure changes, app releases, mergers, or incidents. Many clients choose quarterly or semi-annual cycles.
OSCP, OSCE, GPEN, GWAPT, and CEH certified. We invest in ongoing training and CTF competitions to stay current with evolving attack techniques and emerging threats.
A comprehensive report with executive summary, detailed findings with proof-of-concept evidence, CVSS scores, remediation recommendations, and a strategic roadmap. Plus a debrief call and free retesting of critical findings.
Ready to Find Your Vulnerabilities
Before Attackers Do?
Schedule a free consultation to discuss your testing needs, compliance requirements, and how we can strengthen your security posture.
Our Pen Testing Services
Comprehensive security assessments that expose vulnerabilities across your entire attack surface.
External Network Pen Testing
Simulate attacks against your internet-facing infrastructure — firewalls, VPNs, web servers, and public IPs. We find the vulnerabilities attackers would exploit from the outside.
Internal Network Assessment
Test lateral movement opportunities inside your network. We assess what a compromised employee account or rogue device could access within your environment.
Web Application Testing
OWASP Top 10 testing for web apps and APIs. We test for SQL injection, XSS, authentication flaws, and business logic vulnerabilities in your custom applications.
Wireless Security Testing
Assess your Wi-Fi networks for rogue access points, weak encryption, and authentication bypasses that could give attackers a foothold in your environment.
Social Engineering
Phishing simulations, vishing calls, and physical security tests. We measure your human attack surface and identify training gaps in your security awareness program.
Compliance-Driven Testing
Meet HIPAA, PCI-DSS, SOC 2, CMMC, and NIST compliance requirements with penetration testing that satisfies auditors and gives you actionable remediation guidance.
Why ACS for Penetration Testing
Certified Ethical Hackers
OSCP, CEH, and GPEN certified testers with real-world offensive security experience.
Detailed Reporting
Executive summaries for leadership plus technical deep-dives with proof-of-concept exploits for your IT team.
Remediation Support
We don't just find problems — we help you fix them with prioritized remediation guidance and retesting.
Zero Business Disruption
Testing is performed safely with rules of engagement that protect your production systems.