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Keep Cursor updated against prompt injection

Cursor flaws let prompt injection escape the sandbox · Security incident · X · @blueteamsec1 · Oct 2026

Security news reported critical Cursor flaws where prompt injection could escape the sandbox and run commands.

Lesson

Update Cursor promptly and keep auto-run of terminal commands off for untrusted projects.

Fix prompt

Copy this into your own AI tool (Cursor, Lovable, Claude Code, Bolt…). It's general guidance written by us. Review what the AI suggests before applying it.

I use Cursor, which can read web pages, files, emails or tool output. Help me reduce the risk of prompt injection (hidden instructions in content the AI reads). 1) List what my setup can access (files, terminal, browser, MCP servers, email, databases) and what it can do without asking me. 2) Point out the riskiest combinations, e.g. reading untrusted content while also having access to secrets or the ability to send data out. 3) Suggest concrete settings: require approval for commands and network calls, remove MCP servers I don't need, use read-only tokens, and keep the tool updated. 4) Give me a short checklist to follow before opening untrusted repos or documents. Don't change anything until I've approved your plan. Never ask me to paste API keys, passwords or .env contents; tell me where to check them myself.
Cursor

Source: X ↗

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