CVE-2026-112950

01/Description

Vitest is a Vite-native testing framework for JavaScript and TypeScript projects. From 4.1.11 until 4.1.12 and 5.0.3, isFileLoadingAllowed and the filesystem read interpret backslashes differently on Windows in packages/mocker/src/node/interceptorPlugin.ts. When a client can reach the Vite dev server on Windows and register a redirect mock containing backslash traversal, POSIX joining preserves a Windows backslash traversal that the later filesystem read interprets as a path separator, so the client can read a file outside server.fs.allow that the Vitest process can access. This issue is fixed in versions 4.1.12 and 5.0.3.

02/References6

• github.com/vitest-dev/vitest/commit/15cc006aa9f8683dc5f7e895d01…
• github.com/vitest-dev/vitest/commit/b825313243dc55757e8d7c0f9e7…
• github.com/vitest-dev/vitest/releases/tag/v4.1.12
• github.com/vitest-dev/vitest/releases/tag/v5.0.3
• github.com/vitest-dev/vitest/security/advisories/GHSA-xp26-3454…
• github.com/vitest-dev/vitest/security/advisories/GHSA-xp26-3454…