
Marc Fischer
@marc_r_fischer
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Co-Founder of @InvariantLabsAI, PhD student at ETH Zurich. I care about security and reliability of AI systems. @[email protected]
Zurich, Switzerland
Joined March 2010
Oh wow, more AI malware (uses Claude Code to search for credentials). Is this the exponential takeoff moment people kept mentioning? https://t.co/cJfe1WWO5e
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💙 Big congrats and thanks to the whole team for this small but meaningful milestone. mcp-scan all your servers today and discover all the lethal trifectas near you. Repo: https://t.co/O8zpg9xwUZ
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Great post by @liran_tal @kwhuszcza @marc_r_fischer about the recent JIRA MCP 0-click and how mcp-scan helps you identify similar issues. Since 0.3.5 we now include built-in tools in security scanning. Toxic flow analysis in action. https://t.co/N4zsF86Qsp
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I gave a talk on Wednesday at the Bay Area AI Security Meetup about prompt injection, MCP security and the lethal trifecta. Here are the annotated slides from my presentation, including notes on my weird hobby of trying to coin or amplify new terms of art
simonwillison.net
I gave a talk on Wednesday at the Bay Area AI Security Meetup about prompt injection, the lethal trifecta and the challenges of securing systems that use MCP. It wasn’t …
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😈 BEWARE: Claude 4 + GitHub MCP will leak your private GitHub repositories, no questions asked. We discovered a new attack on agents using GitHub’s official MCP server, which can be exploited by attackers to access your private repositories. creds to @marco_milanta (1/n) 👇
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One of our engineers, Hemang, has created this nice example repo of an MCP Streamable HTTP implementation. This is where things are heading for MCP, post SSE. We are also adding support to Gateway right now. https://t.co/pyRkYLAavi
github.com
Example implementation of MCP Streamable HTTP client/server in Python and TypeScript. - invariantlabs-ai/mcp-streamable-http
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Thanks @ai_risks for the generous prize! AgentDojo is the reference for evaluating prompt injections in LLM agents, and is used for red-teaming at many frontier labs. I had a blast working on this with @edoardo_debe @JieZhang_ETH @marc_r_fischer @lbeurerkellner @mbalunovic
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aaaand we passed 500 stars 🤩 https://t.co/frHJtsELrO
github.com
Constrain, log and scan your MCP connections for security vulnerabilities. - invariantlabs-ai/mcp-scan
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Great write-up of MCP security, including our research from @InvariantLabsAI.
MCP is the hottest thing in AI right now, but people aren't really talking about the security implications... I covered a recently discovered exploit and mitigations on the @thenewstack today: https://t.co/2U7J8WcHnD
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We recently shipped a lot of updates to mcp-scan: - whitelisting of tools - Improvements to the server (reducing false-positives, improving detection) - run via npm/npx Much more coming soon! https://t.co/frHJtsELrO
#mcp
github.com
Constrain, log and scan your MCP connections for security vulnerabilities. - invariantlabs-ai/mcp-scan
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I think Simon raises an important point here. LLM and agent security cannot be solved by a simpler classifier. Instead, Guardrails focuses on detecting guardrail violations on a behavioral level. It analyzes the data flow and active agent context, to make sure, that even if a
@lbeurerkellner It uses this model which isn't fit for purpose - but I don't believe that ANY trained model can credibly detect attacks well enough to be worth recommending https://t.co/dTfi6SQsvt
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4/ How to safeguard? - Make sure only trusted MCP servers are being downloaded and used - Keep minimal funds in your crypto wallet MCP - Allow minimal access for MCP actions - Use MCP-Scan
🚀🔒 We created a security scanner to detect MCP attacks. Please check it out, and give feedback. * Supports Claude, Cursor, Windsurf • Checks for tool poisoning • Checks for rug pull (tool hashing) • Detects cross-origin violations (shadowing) uvx mcp-scan@latest
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Disclaimer: We use Invariant Guardrails server-side via an API and we are collect tool names and descriptions (no personal data). Don't use it if you don't want to share your tools.
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It already supported Claude, Cursor, Windsurf and we just added support for VS Code MPC too.
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uvx mcp-scan@latest Scans your local MCP setup for vulnerabilities. After @lbeurerkellner's recent MCP discoveries, we found it quite important to build. It is open source and out now. Feedback would be greatly appreciated.
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After covering MCP vulnerabilities over the last few days, today, we are launching MCP-scan, a security scanner to detect MCP attacks. Run it now: uvx mcp-scan@latest 🧵
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🚀🔒 We created a security scanner to detect MCP attacks. Please check it out, and give feedback. * Supports Claude, Cursor, Windsurf • Checks for tool poisoning • Checks for rug pull (tool hashing) • Detects cross-origin violations (shadowing) uvx mcp-scan@latest
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🛡️Thoughts on the MCP vulnerability and why it's not an easy fix (1/n) To stay updated about agent security, please follow and sign up for early access to Invariant below. We have been working on this problem for years (at Invariant and in research). https://t.co/eUwik7FNhD
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