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Computer science senior focused on IoT cyber defense

Senior pursuing a CS bachelor's, completing an IoT cyber defense externship at Hydroficient while building practical security and development experience.

Work samples

Portfolio items include coursework, projects, and deliverables from the Hydroficient IoT Cyber Defense externship, focused on IoT security practices and applied development.

  • Cryptanalysis & Frequency Analysis Tool
    Cryptanalysis & Frequency Analysis Tool
    Cryptanalysis & Frequency Analysis Tool

    Developed a C++ cryptanalysis tool to decrypt a 646-character substitution cipher using statistical frequency analysis. Engineered a 6-class object-oriented application that recovered 100% of the original plaintext without the encryption key.

    C++
  • Hydroficient IoT Cyber Defense Externship
    Hydroficient IoT Cyber Defense Externship
    Hydroficient logo

    Hydroficient · ✅ Verified by Extern · ⏱️ In progress

    Hydroficient IoT Cyber Defense Externship

    Build, hack, and defend real IoT infrastructure, then hand your security playbook to an actual company. You’ll launch realistic cyberattacks, from spoofing and replay attacks to unauthorized shutoffs, and implement defenses like TLS and mTLS.

    Python ProgrammingData AnalysisThreat ModelingDashboard Development

About me

Senior pursuing a CS bachelor's, completing an IoT cyber defense externship at Hydroficient while building practical security and development experience.

I am Maria S, a senior studying Computer Science at CUNY John Jay College of Criminal Justice. I have some work experience and I'm completing the Hydroficient IoT Cyber Defense externship while finishing my bachelor's degree.

Externships

Hydroficient IoT Cyber Defense Externship

In progress

Experience

Cybersecurity Researcher 6 Agentic AI & LLMs

John Jay College of Criminal Justice · December 2025 6 Present

Industry Immersion Experience, Technology and AI

Career Learning Lab, John Jay College · February 2026 6 May 2026

Founder

Tuxedo Paw Animal Rescue · January 2024 6 January 2025

Education

John Jay College of Criminal Justice, CUNY Manhattan, New York

Bachelor of Science in Computer Science and Information Security · Class of 2026

Skills

Computer Science fundamentalsIoT security conceptsApplied development for projectsProblem solving from courseworkExternship-based cyber defense tasks

Cryptanalysis & Frequency Analysis Tool

Developed a C++ cryptanalysis tool to decrypt a 646-character substitution cipher using statistical frequency analysis. Engineered a 6-class object-oriented application that recovered 100% of the original plaintext without the encryption key.

C++

Overview

Cryptanalysis & Frequency Analysis Tool
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✅ Verified by Extern · ⏱️ In progress

Hydroficient IoT Cyber Defense Externship

Build, hack, and defend real IoT infrastructure, then hand your security playbook to an actual company. You’ll launch realistic cyberattacks, from spoofing and replay attacks to unauthorized shutoffs, and implement defenses like TLS and mTLS.

Python ProgrammingData AnalysisThreat ModelingDashboard Development

Overview

The externship involved working with an IoT deployment for a marina to evaluate its security posture. The work inspected device interactions, network topology, and service endpoints, then used that understanding to identify exposed components and inform follow-up attack and defense exercises.

Hydroficient IoT Cyber Defense Externship

What I've accomplished

I produced a formal threat-model PDF and a visual threat-model card based on a STRIDE analysis of the Grand Marina water-management system.

Project breakdown

At Hydroficient I analyzed the Grand Marina water system, applied STRIDE to identify threats, made mitigation judgments, and delivered a formal threat-model PDF plus a visual threat-model card as the final deliverable.

During the Project 2 externship, I wrote a Python sensor log generator and published the runnable Colab notebook that simulates water-sensor readings with timestamps and counters for later analysis.

Situation: I needed to build an IoT pipeline and test its weaknesses. Task: construct a broker, publisher, and dashboard and capture traffic. Action: I ran Mosquitto, launched publisher and subscriber clients, intercepted messages with mosquitto_sub, and documented payloads. Result: I captured…

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