XSS in Sylius

CVE-2026-31822

Sylius is an Open Source eCommerce Framework on Symfony. A cross-site scripting (XSS) vulnerability exists in the shop checkout login form handled by the ApiLoginController Stimulus controller. When a login attempt fails, AuthenticationFailureHandler returns a JSON response whose message field is rendered into the DOM using innerHTML, allowing any HTML or JavaScript in that value to be parsed and executed by the browser. The issue is fixed in versions: 2.0.16, 2.1.12, 2.2.3 and above.

Vulnerability class: XSS (Cross-Site Scripting)

Published · last modified .

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.

EPSS exploit prediction

EPSS: 0.003 (19.6th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 20th percentile — 19.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-31822: held from 0.002 to 0.003.

EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001

Affected products

  • Sylius — versions >= 2.2.0, < 2.2.3, >= 2.1.0, < 2.1.12, >= 2.0.0, < 2.0.16

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-31822?
CVE-2026-31822 is a medium-severity vulnerability in Sylius, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-03-10.
How severe is CVE-2026-31822?
Medium severity. CVSS v3 base score is 6.1 out of 10.