What is CVE-2026-21632?

CVE-2026-21632 is a medium-severity vulnerability in Joomla Joomla\!, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2026-04-01.

How severe is CVE-2026-21632?

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

XSS in Joomla Joomla\!

CVE-2026-21632

Lack of output escaping for article titles leads to XSS vectors in various locations.

Vulnerability class: XSS (Cross-Site Scripting)

EPSS: 0.002 (8.9th 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

Joomla Joomla\!
Joomla! Project Cms — versions 4.0.0-5.4.3, 6.0.0-6.0.3

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

security@joomla.org (vendor-advisory, Vendor Advisory)

Frequently asked questions

What is CVE-2026-21632?: CVE-2026-21632 is a medium-severity vulnerability in Joomla Joomla\!, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2026-04-01.
How severe is CVE-2026-21632?: Medium severity. CVSS v3 base score is 5.4 out of 10.