CVE-2026-42211
RCE in React Router Framework Mode via prototype pollution; patch 7.14.2.
Is CVE-2026-42211 being exploited?
Not confirmed. CVE-2026-42211 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 0.42% probability of exploitation in the next 30 days.
How severe is CVE-2026-42211?
CVE-2026-42211 is rated High with a CVSS score of 8.1. 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-2026-42211?
Yes. A fix has been recorded for CVE-2026-42211. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-42211 affect?
CVE-2026-42211 affects React Router Framework Mode (v7.0.0–7.14.1). Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-42211?
Upgrade to 7.14.2 ASAP
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Remote code execution via external requests in Framework Mode; requires a prototype-pollution chain (two steps).
Patch when possible
- affected>= 7.0.0 and < 7.14.2
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.