CVE-2026-90907: CWE-639: Authorization Bypass Through User-Controlled Key in Joomla! Project Joomla! CMS
Joomla! Core - [20260902] - Core - Unauthorized user account creation via profile.save controller in Joomla 1.5.0-5.4.8, 6.0.0-6.1.3 - The profile.save controller did not check the login state of a user, allowing the creation of guest-level users on sites without active user registration.
AI Analysis
Technical Summary
The Joomla! CMS profile.save controller failed to check whether a user was logged in before allowing account creation. This authorization bypass vulnerability (CWE-639) affects Joomla! versions 1.5.0-5.4.8 and 6.0.0-6.1.3. An attacker can exploit this flaw to create guest-level user accounts on sites without active user registration, bypassing intended access controls.
Potential Impact
An attacker can create unauthorized guest-level user accounts on affected Joomla! CMS sites even when user registration is disabled. This could lead to unauthorized access to site resources or functionality restricted to registered users. The vulnerability does not require user interaction or privileges and has a CVSS 4.0 base score of 6.9 (medium severity).
Mitigation Recommendations
Patch status is not yet confirmed — check the Joomla! Project vendor advisory for current remediation guidance. No official fix or patch links are provided in the available data. Until a patch is available, administrators should monitor Joomla! advisories and consider restricting access to the profile.save controller or disabling it if possible.
CVE-2026-90907: CWE-639: Authorization Bypass Through User-Controlled Key in Joomla! Project Joomla! CMS
Description
Joomla! Core - [20260902] - Core - Unauthorized user account creation via profile.save controller in Joomla 1.5.0-5.4.8, 6.0.0-6.1.3 - The profile.save controller did not check the login state of a user, allowing the creation of guest-level users on sites without active user registration.
CVSS v4.0
Score 6.9medium
Affected software
Joomla! Project
Joomla! CMS
pkg:composer/joomla/joomla-cmsRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The Joomla! CMS profile.save controller failed to check whether a user was logged in before allowing account creation. This authorization bypass vulnerability (CWE-639) affects Joomla! versions 1.5.0-5.4.8 and 6.0.0-6.1.3. An attacker can exploit this flaw to create guest-level user accounts on sites without active user registration, bypassing intended access controls.
Potential Impact
An attacker can create unauthorized guest-level user accounts on affected Joomla! CMS sites even when user registration is disabled. This could lead to unauthorized access to site resources or functionality restricted to registered users. The vulnerability does not require user interaction or privileges and has a CVSS 4.0 base score of 6.9 (medium severity).
Mitigation Recommendations
Patch status is not yet confirmed — check the Joomla! Project vendor advisory for current remediation guidance. No official fix or patch links are provided in the available data. Until a patch is available, administrators should monitor Joomla! advisories and consider restricting access to the profile.save controller or disabling it if possible.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- Joomla
- Date Reserved
- 2026-09-14T10:23:04.450Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6abbf0bec9b3d5d17704c4e2
Added to database: 09/29/2026, 17:09:18 UTC
Last enriched: 09/29/2026, 17:15:06 UTC
Last updated: 09/29/2026, 18:00:32 UTC
Views: 5
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