CVE-2026-64642
Auth bypass in Next.js App Router with Turbopack when single locale is configured.
Is CVE-2026-64642 being exploited?
Not confirmed. CVE-2026-64642 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 1.0% probability of exploitation in the next 30 days.
How severe is CVE-2026-64642?
CVE-2026-64642 is rated High with a CVSS score of 8.3. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-64642?
Yes. A fix has been recorded for CVE-2026-64642. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-64642 affect?
CVE-2026-64642 affects Next.js 16.0.0 - 16.2.10, App Router (Turbopack builds), config.i18n.locales with single entry. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-64642?
Upgrade to Next.js 16.2.11 immediately
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Authentication bypass: attackers can craft requests to bypass middleware/proxy auth and access protected routes/data.
Immediate action required
- affected>= 16.0.0 and < 16.2.11
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.