What is CVE-2026-9520?

CVE-2026-9520 is a medium-severity vulnerability in Blitz-js Blitz, classified under Cross-site Scripting. CVSS score: 4.3/10. Published 2026-05-26.

How severe is CVE-2026-9520?

Medium severity. CVSS v3 base score is 4.3 out of 10.

RCE in Blitz-js Blitz

CVE-2026-9520

A weakness has been identified in blitz-js blitz up to 3.0.2 on GitHub. This impacts an unknown function of the file packages/generator/templates/app/src/app/auth/components/LoginForm.tsx of the component Sign-in. This manipulation of the…

Vulnerability class: XSS (Cross-Site Scripting)

EPSS: 0.000 (10.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N.

Affected products

Blitz-js Blitz — versions 3.0.0, 3.0.1, 3.0.2

Weakness classification (CWE)

References

cna@vuldb.com (technical-description, vdb-entry)
cna@vuldb.com (signature, permissions-required)
cna@vuldb.com (third-party-advisory)
cna@vuldb.com (exploit)

Frequently asked questions

What is CVE-2026-9520?: CVE-2026-9520 is a medium-severity vulnerability in Blitz-js Blitz, classified under Cross-site Scripting. CVSS score: 4.3/10. Published 2026-05-26.
How severe is CVE-2026-9520?: Medium severity. CVSS v3 base score is 4.3 out of 10.