XSS in Logto-Io Logto

CVE-2026-54714

Logto is the modern, open-source auth infrastructure for SaaS and AI apps. Prior to 1.41.0, @logto/core reflected the SAML RelayState, SAMLResponse, and actionUrl into a Logto-origin auto-submit HTML form in packages/core/src/saml-application/SamlApplication/utils.ts without HTML-attribute escaping. A SAML application flow with a crafted RelayState from GET or POST /api/saml/:id/authn could inject script that runs on the Logto tenant origin after the user completes login. This issue is fixed in version 1.41.0.

Vulnerability class: XSS (Cross-Site Scripting)

EPSS: 0.003 (26.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-54714?
CVE-2026-54714 is a medium-severity vulnerability in Logto-Io Logto, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-07-10.
How severe is CVE-2026-54714?
Medium severity. CVSS v3 base score is 6.1 out of 10.