Vitest is a testing framework powered by Vite. From 5.0.0-beta.6 until 5.0.5, Vitest dev servers can misapply server.fs.deny because project servers replace Vite's defaults and the root server adds .vitest-secret-token after Vite compiles its matcher. An attacker who can reach an affected UI, Browser Mode, or API server can read denied project files or the fallback API token at nodemodules/.vitest/.vitest-secret-token, and Browser Mode with test.projects can expose JavaScript-compatible .env values through a malicious website. This issue is fixed in version 5.0.5.