Penetration testing remains one of the most effective ways to evaluate the real-world security posture of an organization's digital assets. Unlike automated vulnerability scanning, a proper pentest simulates the tactics, techniques, and procedures (TTPs) of actual threat actors. At Nexis Limited, we employ industry-standard methodologies to deliver actionable security assessments for businesses across Bangladesh and beyond.
Understanding Penetration Testing Frameworks
Two dominant frameworks guide modern penetration testing: the Penetration Testing Execution Standard (PTES) and the OWASP Testing Guide. PTES defines seven phases—pre-engagement interactions, intelligence gathering, threat modeling, vulnerability analysis, exploitation, post-exploitation, and reporting. The OWASP Testing Guide, now in version 4.2, provides a granular checklist of over 90 test cases specifically for web applications. A mature testing program combines both frameworks to ensure comprehensive coverage.
Phase 1: Reconnaissance and Intelligence Gathering
Reconnaissance is the foundation of any penetration test. Passive reconnaissance involves collecting publicly available information without directly interacting with the target—WHOIS records, DNS enumeration, certificate transparency logs, and OSINT from social media and job postings. Tools like Shodan, Censys, and theHarvester automate much of this process. Active reconnaissance escalates to direct interaction: port scanning with Nmap, service fingerprinting, and directory brute-forcing with tools like Gobuster or Feroxbuster. The goal is to map the attack surface comprehensively before any exploitation begins.
DNS and Subdomain Enumeration
Subdomain discovery frequently reveals forgotten staging environments, legacy applications, and internal tools exposed to the internet. Techniques include DNS zone transfer attempts, certificate transparency log mining via crt.sh, and brute-force enumeration using wordlists. In the Bangladeshi market, we frequently encounter organizations with dozens of unmonitored subdomains running outdated software—each representing a potential entry point for attackers.
Phase 2: Vulnerability Analysis
Once the attack surface is mapped, systematic vulnerability analysis begins. This combines automated scanning using tools like Nessus, OpenVAS, or Nuclei with manual testing for logic flaws that scanners miss. Common findings include outdated software with known CVEs, misconfigured TLS implementations, exposed administrative interfaces, and default credentials. Each vulnerability is validated manually to eliminate false positives before proceeding to exploitation.
Phase 3: Exploitation and Post-Exploitation
Exploitation demonstrates the real-world impact of identified vulnerabilities. This might involve exploiting an SQL injection to extract database contents, leveraging a deserialization vulnerability for remote code execution, or chaining multiple low-severity findings into a critical attack path. Post-exploitation focuses on lateral movement, privilege escalation, and data exfiltration simulation. The objective is not simply to gain access, but to demonstrate what an attacker could achieve with that access—quantifying business risk in concrete terms.
Reporting and Remediation Guidance
The deliverable of a penetration test is only as valuable as its report. A professional report includes an executive summary for non-technical stakeholders, detailed technical findings with proof-of-concept evidence, risk ratings using CVSS scoring, and prioritized remediation recommendations. Each finding should include reproduction steps, screenshots, and specific fix guidance. We also recommend retesting after remediation to verify that fixes are effective and haven't introduced new vulnerabilities.
Organizations in Bangladesh face an evolving threat landscape, and periodic penetration testing is no longer optional—it's a business necessity. Whether you're securing a financial application, an e-commerce platform, or internal infrastructure, a methodical approach to security testing is the first step toward genuine resilience. Contact us to discuss how our security assessment services can strengthen your defenses.