What is CVE-2026-33244?

CVE-2026-33244 is a medium-severity vulnerability in Remix-run React-router, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2026-06-02.

How severe is CVE-2026-33244?

Medium severity. CVSS v3 base score is 5.4 out of 10.

XSS in Remix-run React-router

CVE-2026-33244

React Router is a router for React. In versions 7.5.1 through 7.13.1, when using Framework Mode with pre-rendering enabled, improper neutralization of the HTTP `Location` header value can permit Cross-Site Scripting (XSS) in the statically…

Vulnerability class: XSS (Cross-Site Scripting)

EPSS: 0.000 (9.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N.

Affected products

Remix-run React-router — versions >= 7.5.1, < 7.13.2
Shopify React-router

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

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

Frequently asked questions

What is CVE-2026-33244?: CVE-2026-33244 is a medium-severity vulnerability in Remix-run React-router, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2026-06-02.
How severe is CVE-2026-33244?: Medium severity. CVSS v3 base score is 5.4 out of 10.