CVE-2026-21629 Joomla! Core - [20260301] - ACL hardening in com_ajax
The Joomla ajax component lacked default logged-in-user checks in the admin area, allowing unauthorized access to administrative functions.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-21629?
CVE-2026-21629 is a medium-severity missing authorization vulnerability in Joomla Joomla\!, published on 1 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
The ajax component was excluded from the default logged-in-user check in the administrative area. This behavior was potentially unexpected by 3rd party developers.
Weakness: CWE-284
Which versions are affected by CVE-2026-21629?
1 open source package ship an affected version, including joomla. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
joomla Bitnami | From 3.0.0 | 5.4.4, 6.0.4 |
Products include Joomla Joomla\!.
How do I fix CVE-2026-21629?
Upgrade joomla to a fixed version for your release line: 5.4.4 or 6.0.4.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-21629 being exploited?
There is no known exploitation of CVE-2026-21629 in the wild and no public exploit code.
Other vulnerabilities in Joomla Joomla\!
- CVE-2016-10033 PHPMailer Command Injection
- CVE-2023-23752 Joomla! Improper Access Control
- CVE-2026-48902 Joomla! Core - [20260518] - Transport encryption downgrade for password and username reset links
- CVE-2025-25226 [20250401] - Joomla Framework - SQL injection vulnerability in quoteNameStr method of Database package
- CVE-2022-23795 [20220303] - Core - User row are not bound to a authentication mechanism
Sources
Also known as BIT-joomla-2026-21629, GHSA-cvwg-67gg-j4gg.