Advisories for Npm/@Vitest/Mocker package

2026

Vitest: Windows backslash traversal bypasses the @vitest/mocker redirect allowlist fix

The path traversal fix released for GHSA-82fw-gwwq-j7x9 can be bypassed on Windows by using a backslash in the redirect URL pathname. The fixed code joins an attacker-controlled URL pathname with the Vite root using node:path/posix, then passes that string to Vite's file allowlist check. On Windows, a value such as C:/project/root/..\secret.txt retains ..\ during the POSIX join and begins with the allowed root, so the allowlist accepts it. The later …

Vitest: Code injection via unauthenticated manual mock registration

@vitest/mocker's interceptorPlugin accepts mock registrations on Vite's dev-server WebSocket with no authentication, and interpolates the mock's url into generated module source without escaping. A client that can reach the dev server can make it serve arbitrary JavaScript in place of any project module, which then runs in the developer's browser on the dev-server origin. Same handler and same unauthenticated caller as GHSA-82fw-gwwq-j7x9; that fix (8ff9b9a9efca7c6cfd5243569440de8d7a33aec4, PR #10972) hardened only the …

Vitest: Path Traversal / Arbitrary File Read via @vitest/mocker Redirect Mock

@vitest/mocker registers a redirect mock's target path without validating it against the dev server's file-serving allowlist. An attacker who can reach the dev server's WebSocket can register a redirect mock pointing outside the project root; when the mocked module is requested, the plugin's load hook returns readFile(<attacker path>) as the module source, disclosing local files. This is exploitable without authentication only through the public mockerPlugin / standalone interceptorPlugin exports (used …