
๐ Spring4Shell Firewall Defense โ Cybersecurity Incident Simulation This project is part of a Cybersecurity Job Simulation I completed in August 2025 through Forage. It focuses on detecting, analyzing, and mitigating a simulated real-world cyberattack involving the Spring4Shell (CVE-2022-22965) vulnerability
๐ก๏ธ Spring4Shell Firewall Defense โ Cybersecurity Incident Simulation This project is part of a Cybersecurity Job Simulation I completed through Forage in August 2025. It simulates a real-world incident involving the Spring4Shell (CVE-2022-22965) vulnerability and demonstrates how a custom firewall can detect and mitigate exploitation attempts.
๐ Project Overview The goal of this simulation was to identify and block malicious traffic targeting a vulnerable web application endpoint. I developed a custom Python-based HTTP firewall that monitors and filters incoming requests, detecting known exploit patterns and stopping them in real time.
๐งฐ Key Features ๐ Threat Detection: Analyzes HTTP POST data for suspicious keys and payloads.
๐ Firewall Defense: Blocks malicious requests using pattern-based rules.
๐ฃ Exploit Prevention: Detects attempted remote code execution via Runtime.getRuntime() and similar signatures.
๐ Logging & Monitoring: Displays blocked attempts and reasons for blocking in the terminal.
๐ผ๏ธ Demo In the first screenshot, a suspicious POST request attempts to exploit the Spring4Shell vulnerability by injecting a payload with Runtime.getRuntime(). The custom firewall immediately detects this pattern and blocks the request, returning a 403 Forbidden response โ effectively stopping a potential Remote Code Execution (RCE) attempt.

In contrast, the second screenshot shows a safe POST request with harmless data (username=test) sent to the server. The firewall recognizes it as safe and allows the request to pass through, returning a standard 200 OK response. This highlights the firewallโs ability to distinguish between normal and malicious activity with precision.

๐งช Technologies Used Python (firewall implementation)
http.server module for simulating vulnerable server
curl for simulating POST requests
Custom signature detection logic
๐ What I Did Analyzed a simulated Spring4Shell attack targeting a JSP endpoint.
Identified suspicious payloads in POST data.
Wrote a custom firewall (firewall_server.py) to detect and block malicious requests.
Validated the firewall by simulating attacks (see screenshot).
Documented the incident with a detailed postmortem analysis.
๐ Certificate RNhbu8QnDzthwynEf_M6JGAwZ52SMusMEcK_cKqCaSyzkPoWXRdg5_1754434963290_completion_certificate.pdf