Next.js is a React framework. Starting with version 12.0.0 and prior to version 12.0.9 vulnerable code could allow a bad actor to trigger a denial of service attack for anyone using i18n functionality. In order to be affected by this CVE one must use next start or a custom server and the built-in i18n support. Deployments on Vercel along with similar environments where invalid requests are filtered before reaching Next.js are not affected. A patch has been released `next@12.0.9` that mitigates this issue. As a workaround one may ensure `/${locale}/_next/` is blocked from reaching the Next.js instance until it becomes feasible to upgrade.