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> security_researcher --status active

Securing systems.
Breaking assumptions.

Computer Science graduate from Manhattan University with a focus on cybersecurity, network defense, and secure application development. Trilingual professional protecting critical infrastructure.

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// about

Security Mindset

Network Defense

Proficient in network monitoring with Wireshark, firewall configuration, and intrusion detection systems. Understanding how traffic flows to identify and stop threats before they escalate.

Authentication & Access Control

Built production OAuth 2.0 authentication systems with MFA, Firebase integration, and secure session management. Protecting user identity at every entry point.

Operating System Security

Deep understanding of Linux kernel security, OS hardening, and administration. Experienced with Seed Labs for hands-on exploitation and defense exercises.

Secure Development

Writing secure code from the start — input validation, encrypted communications, and defense-in-depth principles applied across Python, JavaScript, and C++ applications.

"Security isn't just about building walls — it's about understanding how they're breached and making them stronger every time."

// arsenal

Security Toolkit

Languages

Python JavaScript TypeScript C++ SQL Bash Java HTML/CSS

Security & Infrastructure

Wireshark Seed Lab Linux (Kernel/OS) Firebase Auth Docker Azure DevOps Git / GitHub / GitLab REST APIs Hardware/IT

ML / AI

Qdrant Pinecone HuggingFace RAG LangChain Prompt Engineering Semantic Search Lightning.ai

Frameworks & Platforms

Node.js Express.js Passport.js SQLite Vercel MacOS

// projects

Security Projects

CMPT 369 — Cybersecurity Lab

Google OAuth 2.0 Authentication Service

Engineered a standalone OAuth 2.0 verification API with multi-factor authentication and session security — hardening user account protection from the ground up.

  • Built OAuth 2.0 verification API using Express.js and google-auth-library
  • Integrated Firebase Authentication for MFA step verification
  • Configured secure routing redirects, session serialization, and backend auth checks
  • Protected dashboard endpoints with layered security controls
Node.js Express Google Auth Firebase Passport.js
SECURITY LEVEL
HIGH
CMPT 490 — Capstone

Turkey.app — Secure Image Platform

Full-stack web application for secure image storage, organization, and semantic search — with user authentication, access control, and storage capacity management.

  • Agile/Scrum development in a 4-member team at Manhattan University
  • Implemented backend auth, storage capacity management, and image import/export
  • Semantic search powered by Qdrant vector database
  • Sprint planning, feature delivery, and backlog management
Python SQLite Qdrant Lightning.ai
SECURITY LEVEL
MODERATE
CMPT 456 — Software Engineering

College Application Tracker (CAT)

Web application with secure OAuth 2.0 authentication protecting student data — university search, deadline tracking, and automated reminders built with privacy-first design.

  • 3-member team project focused on student privacy and data security
  • OAuth 2.0 implementation protecting user authentication flows
  • Personalized university search with individual user story matching
  • Automated deadline reminders with secure notification system
HTML CSS JavaScript OAuth 2.0
SECURITY LEVEL
ELEVATED

// lab_exercises

Hands-on Security Labs

> SEED LAB 01

Wireshark Packet Analysis

Monitored and captured live network traffic to analyze packet structures, identify suspicious communication patterns, trace UDP/TCP streams, and inspect protocol headers.

> SEED LAB 02

Software Vulnerability Exploits

Executed buffer overflow attacks inside isolated Linux environments to overwrite stack variables, alter program execution control flow, and execute arbitrary root-level shellcode.

> SEED LAB 03

Web Authentication Exploitation

Leveraged injection techniques like SQL injection to bypass application login logic and retrieve sensitive DB rows, and Cross-Site Scripting (XSS) to capture user session tokens.

> SEED LAB 04

OS Hardening & Access Audits

Investigated privilege escalation vulnerabilities, analyzed Set-UID programs to understand boundary-crossing safety, and audited system configurations to mitigate host exploitation.

// certifications

Credentials & Training

Cybersecurity Upskilling & Frameworks

LinkedIn Learning

Mar 2025

Securing Cryptocurrencies

LinkedIn Learning

Apr 2025

Operating Systems: Overview, Admin & Security

IBM

Nov 2022

Cybersecurity Roles, Processes & OS Security

Coursera

Nov 2022

Product Management Job Simulation

Electronic Arts (Forage)

Apr 2026

Personal Banker Job Simulation

Wells Fargo (Forage)

Apr 2026

// coursework

Relevant Studies

CMPT 369

Cybersecurity Lab

Hands-on security exercises: penetration testing, vulnerability analysis, authentication systems, and network defense.

CMPT 456

Software Engineering

Secure software development lifecycle, Agile methodologies, OAuth implementation, and team-based project delivery.

CMPT

Computer Security

Cryptography, access control models, malware analysis, and security protocols for modern computing environments.

CMPT

Operating Systems

Process management, memory protection, kernel security, file system permissions, and OS-level hardening techniques.

CMPT

Data Structures & Algorithms

Efficient data handling, algorithmic complexity, and optimization — foundational to writing secure and performant code.

// contact

Let's Connect

Joseph Decossard

Computer Science • Manhattan University '26

English · French · Creole (Trilingual)

jedecossard@gmail.com LinkedIn GitHub (Personal) GitHub (School)
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