Introduction
This wasn’t a “got root 😎” kind of week—it was a produce a report that changes behavior kind of week.
Target: an Ubuntu Linux host in a contained lab. Toolbelt: Nmap for recon, Nessus for vuln discovery, Metasploit for tightly-scoped exploitation, plus local enumeration, credential hygiene checks, and careful evidence capture.
Deliverable: a thorough, reproducible penetration testing report with risk ratings, proofs-of-impact, and remediation steps the team could ship.
What I Set Out to Deliver
- Clear scope & rules of engagement: what’s in, what’s out, test windows, and stop conditions.
- Reproducible findings: screenshot + hash + context; no “trust me.”
- Proven impact: controlled exploitation to demonstrate risk, not create it.
- Business mapping: what each issue means for data, operations, and reputation.
- Remediation you can actually do: prioritized fixes, validation steps, and owners.
Scope & Guardrails
- In-scope asset: single Ubuntu server (lab).
- Allowed techniques: network recon, authenticated/unauthenticated service checks, safe exploitation in isolation, local enumeration, password hygiene auditing.
- Disallowed: data exfiltration beyond minimal proof, lateral movement (except to show possible ways I can do it), DoS, persistence.
- Safety: snapshots, read-only where possible, immediate cleanup, logged timestamps.
Method at a Glance
- Recon & Mapping: service inventory with Nmap; verify banners and versions.
- Vulnerability Discovery: scanner corroboration (Nessus) + manual validation.
- Exploitation (Scoped): demonstrate impact on select, confirmed issues (e.g., legacy FTP module exposure, residual backdoor behavior, PHP CGI misconfig).
- Post-Exploitation: minimal-footprint enumeration, privilege escalation checks, data-access boundaries.
- Credential Hygiene: password policy audit, hash review, weak/guessable patterns.
- Evidence & Reporting: screenshots, commands, hashes, timestamps, and clear repro steps.
Recon: Turning the Network into a Map
Goal: make unknowns boring.
I built a service map (ports, protocols, versions), flagged anomalies, and identified trust boundaries (what talks to what, and why). Findings fed the test plan—no exploitation without a rationale.
What I captured:
- Port/service matrix (with version confidence levels)
- Host fingerprints and OS hints
- First-pass risk flags (old FTP daemon, legacy web handler)
Vulnerability Discovery: Corroborate, Don’t Guess
Scanners are advisors, not oracles. I cross-checked results against manual probes to avoid false positives. Three classes of issues made the shortlist for proof:
- Legacy FTP module exposure (e.g., copy/write misuse): file-system impact risk.
- Residual backdoor behavior: signs of a bind-style shell/backdoor leftover; investigated scope and viability.
- PHP CGI misconfiguration: request handling that could enable unintended code paths.
For each candidate, I logged: affected service, preconditions, data at risk, and safe proof path.
Exploitation (Controlled Proofs Only)
Purpose: show impact, not show off. I used a private, isolated workflow to demonstrate one carefully-chosen path per issue—just enough to convince an engineer and a risk owner. Proofs stayed minimal: environment details, the smallest reproducible action, and the exact guardrails I used.
Safeguards I enforced:
- Snapshots and no persistence
- Only the data needed to prove the finding
- Immediate rollback and artifact cleanup
Post-Exploitation & Privilege Escalation (Minimal Footprint)
Once a low-priv foothold was demonstrated, I kept it surgical:
- Enumerated OS/kernel, groups, PATH, SUID/SGID, scheduled tasks, and service configs.
- Checked for misconfig ladders (world-writable paths, stale sudo rules, weak service ownership).
- Documented a plausible path to elevated access where applicable, with impact statements (not step-by-step weaponization).
Credential & Password Hygiene
I reviewed hashing algorithms, rotation signals, and basic policy strength indicators. The focus was risk patterns, not trophy cracking: weak defaults, reuse hints, and where rate-limits and lockouts were effective or missing. Each note became a policy-level recommendation the team could implement without heroics.
Evidence, Reproducibility, and Chain of Custody
Every finding included:
- Context: where I was, what preconditions existed
- Exact inputs: commands/requests (redacted as needed)
- Outputs: screenshots + hashes + timestamps
- Cleanup: how I reverted or neutralized the test
Risk Ratings & Business Impact
I used consistent language so engineering and leadership could agree on “why this matters.”
- Backdoor behavior (bind-style shell): Critical — integrity/control risk; immediate containment & forensic follow-up.
- FTP module exposure (file copy/write misuse): High — path to file tampering or credential exposure; disable module or harden config.
- PHP CGI misconfig: Medium–High — request-routing pitfalls with potential code execution; standardize handler config and update.
Each item mapped to CVSS-style reasoning, affected assets, and time-to-fix estimates.
Remediation (Prioritized & Practical)
- Contain & verify integrity where backdoor behavior is suspected (service binaries, timers, unknown listeners).
- Harden or remove legacy modules; least-privileged service accounts; write-protect sensitive paths.
- Normalize web handler configs; pin versions; add request filtering and provenance checks.
- Credential policy tune-up: stronger defaults, rate limits, unique admin paths, and alerting.
- Validation plan: after each fix, re-run the smallest proof to confirm closure.
Report Structure That Shipped
- Executive Summary: three sentences, one table.
- Methodology: what I tested and what I avoided.
- Findings: one page per issue (impact → proof → evidence → remediation).
- Appendix: raw artifacts, hashes, timelines, and cleanup notes.
Lessons I’m Keeping
- Write the report as you test. Don’t save documentation for Friday.
- Validate early, escalate carefully. One clean proof beats five messy demos.
- Scope protects everyone. Guardrails make it safe to learn and to fix.
- Make engineers the hero. Findings are only good if they’re fixable.
What’s Next
- Automate artifact hashing and timestamps during capture.
- Reusable finding templates and severity guardrails.
- Add lightweight purple-team validations so fixes get verified continuously.
Why This Matters
Pen testing isn’t about clever shells—it’s about changing the security posture. A thoughtful report translates technical wins into operational wins: fewer unknowns, clearer ownership, and a plan that survives Monday morning.