XSS in Sensiolabs Symfony

CVE-2026-48761

Symfony is a PHP framework for web and console applications and a set of reusable PHP components. From 6.1.0 until 6.4.41, 7.4.13, and 8.0.13, UrlAttributeSanitizer::getSupportedAttributes() omitted URL-bearing attributes on <object>, <applet>, <iframe>, and <img>, and <meta http-equiv="refresh"> URLs inside content bypassed URL sanitization, allowing explicitly enabled elements or attributes to pass javascript: and similar payloads into sanitized output. This issue is fixed in versions 6.4.41, 7.4.13, and 8.0.13.

Vulnerability class: XSS (Cross-Site Scripting)

EPSS: 0.003 (27.1th 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-2026-48761?
CVE-2026-48761 is a medium-severity vulnerability in Sensiolabs Symfony, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-07-14.
How severe is CVE-2026-48761?
Medium severity. CVSS v3 base score is 6.1 out of 10.