# Vitest v4.1.2 — Release & Upgrade Intelligence
- **Product:** Vitest (https://vitest.dev)
- **Version:** v4.1.2
- **Released:** Mar 26, 2026
- **Impact Score:** 5/10
- **Breaking Changes:** Not verified
- **Canonical Analysis:** https://changelogs.us/vitest/updates/v4.1.2/

## Executive Summary (TL;DR)
Vitest v4.1.2. Source highlight: This release bumps Vitest's `flatted` version and removes version pinning to resolve `flatted`'s CVE related issues (https://github.com/vitest-dev/vitest/issues/9975).

## Bug Fixes
- Don't resolve `setupFiles` from parent directory &nbsp;-&nbsp; by @hi-ogawa in https://github.com/vitest-dev/vitest/issues/9960 <samp>(7aa93)</samp>
- Ensure sequential mock/unmock resolution &nbsp;-&nbsp; by @hi-ogawa and **Claude Opus 4.6** in https://github.com/vitest-dev/vitest/issues/9830 <samp>(7c065)</samp>
- **browser**: Take failure screenshot if `toMatchScreenshot` can't capture a stable screenshot &nbsp;-&nbsp; by @macarie in https://github.com/vitest-dev/vitest/issues/9847 <samp>(faace)</samp>
- **coverage**: Correct `coverageConfigDefaults` values and types &nbsp;-&nbsp; by @Arthie in https://github.com/vitest-dev/vitest/issues/9940 <samp>(b3c99)</samp>
- **pretty-format**: Fix output limit over counting &nbsp;-&nbsp; by @hi-ogawa in https://github.com/vitest-dev/vitest/issues/9965 <samp>(d3b7a)</samp>
- Disable colors if agent is detected &nbsp;-&nbsp; by @sheremet-va and @AriPerkkio in https://github.com/vitest-dev/vitest/issues/9851 <samp>(6f97b)</samp>