What is CVE-2026-34077?

CVE-2026-34077 is a high-severity vulnerability in Remix-run React-router, classified under Allocation of Resources Without Limits or Throttling. CVSS score: 7.5/10. Published 2026-06-02.

How severe is CVE-2026-34077?

High severity. CVSS v3 base score is 7.5 out of 10.

Resource exhaustion in Remix-run React-router

CVE-2026-34077

React Router is a router for React. In versions 7.7.0 through 7.13.1, when using React Router's unstable React Server Components (RSC) APIs, there is a potential client-side Cross-Site Scripting (XSS) vulnerability in the RSC redirect hand…

EPSS: 0.000 (12.3th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Remix-run React-router — versions >= 7.0.0, < 7.14.0
Remix-run Turbo-stream — versions < 3.0.0
Shopify React-router
Turbo-stream Turbo_stream

Weakness classification (CWE)

CWE-770 — Allocation of Resources Without Limits or Throttling

References

security-advisories@github.com (x_refsource_CONFIRM, Vendor Advisory)

Frequently asked questions

What is CVE-2026-34077?: CVE-2026-34077 is a high-severity vulnerability in Remix-run React-router, classified under Allocation of Resources Without Limits or Throttling. CVSS score: 7.5/10. Published 2026-06-02.
How severe is CVE-2026-34077?: High severity. CVSS v3 base score is 7.5 out of 10.