What is CVE-2024-21729?

CVE-2024-21729 is a medium-severity vulnerability in Joomla Joomla\!, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2024-07-09.

How severe is CVE-2024-21729?

Medium severity. CVSS v3 base score is 6.1 out of 10.

XSS in Joomla Joomla\!

CVE-2024-21729

Inadequate input validation leads to XSS vulnerabilities in the accessiblemedia field.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2024-07-09 · last modified 2026-06-17.

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: 0.004 (36.0th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 36th percentile — 36.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000

Affected products

Joomla Joomla\!
Joomla! Project Cms — versions 4.0.0-4.4.5, 5.0.0-5.1.1

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

developer.joomla.org/security-centre/935-20240701-core-xss-in-accessible-media-… (vendor-advisory, Vendor Advisory)

Frequently asked questions

What is CVE-2024-21729?: CVE-2024-21729 is a medium-severity vulnerability in Joomla Joomla\!, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2024-07-09.
How severe is CVE-2024-21729?: Medium severity. CVSS v3 base score is 6.1 out of 10.