Master Smart Contract Security with Hands-On Vulnerability Lab

Master Smart Contract Security with Hands-On Vulnerability LabMaster Smart Contract Security with Hands-On Vulnerability Lab

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Amna Nasir

• Apr 19

Smart Contract Vulnerability Lab

Developed a hands-on smart contract security lab to demonstrate real-world vulnerabilities in Ethereum-based applications. This project focuses on understanding how common exploits occur, how attackers take advantage of them, and how to prevent such issues in production smart contracts.

The lab includes multiple vulnerability scenarios, each with a vulnerable contract, an attacker implementation, and an execution script to simulate real attack conditions.

Key Features

Demonstrates real-world smart contract vulnerabilities

Includes attacker contracts to simulate exploits

Provides executable scripts for testing attacks

Structured for learning and practical understanding

Vulnerabilities Covered

Reentrancy Attack

Access Control Vulnerability

tx.origin Authentication Flaw

Integer Overflow / Underflow

Tech Stack

Solidity

Hardhat

Ethers.js

JavaScript

Key Learnings

Smart contract vulnerabilities are often caused by logical flaws

Execution order and external calls can introduce critical risks

Proper access control is essential for contract security

Secure design patterns like Checks-Effects-Interactions are crucial

Project Link: https://github.com/bizzorotical-ank01/smart-contract-vulnerability-lab

Hardhat Blockchain Development Solidity Ethereum JavaScript

Olly Smith

• Apr 29

IMPOSSIBLE.UI — LUMEN Protocol I built a full-screen “Impossible UI” where the interface behaves like a living control system instead of a webpage. The experience boots in real time, typography magnetizes to cursor movement, and a reactive HUD orchestrates layered motion around a live Rive character. What makes it feel “unbuildable” is the choreography: every layer (cursor, ambient light, glitch text, radar rings, scan systems, and hold-to-commit core) responds simultaneously with film-like timing, breaking traditional section-based UI behavior.

Website CSS Web Design Web Development CSS3 JavaScript impossibleuiwithrive Rive web

Bob Vasic

pro

• Apr 27

This is The Signal Room, my Zo Computer Challenge submission, live at zo.contrabob.pro. I built it in Zo Computer as an AI-native personal website that acts like a founder and security command center instead of a static portfolio. Visitors enter a SOC-style room, called SIGNAL ROOM, generate a custom clearance badge, unlock the system through a hidden 1337 console easter egg, and run a Signal Scan on their company or idea. The result is an AI-powered Signal Brief with a Signal Score, positioning diagnosis, trust gap, revenue wedge, security risk, and fastest MVP move. It also includes avatar interaction, Stripe-ready Signal Audit monetization, Telegram lead logic, API-ready website analysis, gamification, sharing, and demo mode. The web application is using real API services for security screenings and high-level security audits, so please use it responsibly. The goal was to show what a personal website becomes on Zo Computer: a live operator system. Video with the walktrough as per submission requirements is in the web application itself. LinkedIn URL: https://www.linkedin.com/posts/bobvasic_zocomputerchallenge-share-7454422972137811968-VGpS?utm_source=social_share_send&utm_medium=member_desktop_web&rcm=ACoAAAWbOcYBym9kgZZll4IyyFfT9tR-b1MMg5U X.com URL: https://x.com/bobvasx/status/2048656752111988960?s=20 Kind regards, Bob