CVE-2026-90917 Joomla! Core - [20260907] - Core - Improper ACL checks in outputs for tagged items in Joomla 4.0.0-5.4.8, 6.0.0-6.1.3
Unauthorized users can view content from inaccessible categories due to improper ACL checks in Joomla core.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-90917?
CVE-2026-90917 is a medium-severity missing authorization vulnerability in Joomla Joomla\!, published on 29 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Joomla! Core - [20260907] - Core - Improper ACL checks in outputs for tagged items in Joomla 4.0.0-5.4.8, 6.0.0-6.1.3 - An improper access check allows unauthorized users to view content items from inaccessible categories.
Weakness: CWE-284
Which versions are affected by CVE-2026-90917?
1 open source package ship an affected version, including joomla. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
joomla Bitnami | From 4.0.0 | 5.4.8, 6.1.3 |
Products include Joomla Joomla\!.
How do I fix CVE-2026-90917?
Upgrade joomla to a fixed version for your release line: 5.4.8 or 6.1.3.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-90917 being exploited?
There is no known exploitation of CVE-2026-90917 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-2026-90917, GHSA-4xw6-jw26-gp2r.