Post #3147012

OWASP rates XSS as high frequency, low impact. That was before webMCP. Any JavaScript on a page can register tools with the browser's LLM — including injected payloads. The model trusts both. We validated a full kill chain from injection to C2 exfiltration in five minutes. Defenses exist, but need more than 500 characters. Full writeup: https://blog.arachnovato.com/script-injection-makes-webmcp-a-force-multiplier-for-attackers/ #security #webmcp #mcp #ai