MCPwner AI Pentesting Tool Finds Multiple 0-Day Vulnerabilities in OpenClaw
What MCPwner Is
MCPwner is an MCP (Model Context Protocol) server that enables AI agents to conduct automated penetration testing against security targets. The developer built it to orchestrate older AI models like GPT-4o and Claude 3.5 Sonnet, which when properly directed through MCPwner can find deep architectural flaws that standard scanning tools miss.
Recent OpenClaw Findings
When pointed at OpenClaw, MCPwner successfully identified multiple 0-day vulnerabilities that have now received official advisories. These weren't just minor bugs but critical security issues:
- Environment Variable Injection
- ACP permission auto-approval bypass
- File-existence oracle information disclosure
- safeBins stdin-only bypass
The tool found logic bypasses and injection points that traditional static analysis tools completely overlooked.
Technical Approach
MCPwner demonstrates that mid-tier and older AI models, when properly orchestrated through this MCP server, can outperform traditional static analysis for vulnerability discovery. The project has already identified multiple vulnerabilities and other CVEs beyond the OpenClaw findings.
Project Status and Contribution
The project is still in active development but already producing results. The developer is seeking contributors to help sharpen the scanning logic and expand the toolkit. Pull requests and feedback are welcome, particularly from those building in the offensive AI space who want to test the tool.
GitHub repository: https://github.com/Pigyon/MCPwner
📖 Read the full source: r/openclaw
👀 See Also
Windows Notepad App Remote Code Execution Vulnerability CVE-2026-20841
CVE-2026-20841 is a remote code execution vulnerability in the Windows Notepad app. Details and mitigation steps are available in the Microsoft Security Response Center update guide.
AI Security Researchers: Your 0-Day Vulnerabilities May Leak via Data Opt-In Toggle
The 'Improve the model for everyone' toggle in LLM interfaces can automatically harvest deep red-teaming research, sending your vulnerability concepts to vendor safety teams and potentially to academic papers before you publish. Disable data sharing before conducting serious security research.
Supply-chain attack uses invisible Unicode code to bypass detection
Researchers discovered 151 malicious packages uploaded to GitHub from March 3-9 using invisible Unicode characters to hide malicious code. The attack targets GitHub, NPM, and Open VSX repositories with packages that appear legitimate but contain hidden payloads.
Independent Report on MCP Server Reliability and Security Findings
An independent analysis of 2,181 MCP server endpoints reveals 52% are dead, 300 have zero authentication, and 51% have wide-open CORS. The report includes methodology and a testing tool.