CVE-2026-48958: CWE-284 Improper Access Control in Joomla! Project Joomla! CMS
An improper access check allows unauthorized users to create custom fields via webservices endpoints.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-48958) in Joomla! CMS arises from improper access checks (CWE-284) that permit unauthorized users to create custom fields through webservices endpoints. The flaw affects multiple versions spanning 4.0.0 to 5.4.6 and 6.0.0 to 6.1.1. The CVSS 4.0 base score is 6.4, indicating a medium severity with network attack vector, low attack complexity, and no user interaction required. The vulnerability has been published but no official fix or patch is currently available, and no known exploits in the wild have been reported.
Potential Impact
Unauthorized users can create custom fields in Joomla! CMS via webservices endpoints due to improper access control. This could lead to unauthorized modifications of the CMS configuration or data structure, potentially impacting the integrity and security of the affected Joomla! installations.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is released, restrict access to webservices endpoints and monitor for suspicious activity related to custom field creation.
CVE-2026-48958: CWE-284 Improper Access Control in Joomla! Project Joomla! CMS
Description
An improper access check allows unauthorized users to create custom fields via webservices endpoints.
CVSS v4.0
Score 6.4medium
Affected software
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
This vulnerability (CVE-2026-48958) in Joomla! CMS arises from improper access checks (CWE-284) that permit unauthorized users to create custom fields through webservices endpoints. The flaw affects multiple versions spanning 4.0.0 to 5.4.6 and 6.0.0 to 6.1.1. The CVSS 4.0 base score is 6.4, indicating a medium severity with network attack vector, low attack complexity, and no user interaction required. The vulnerability has been published but no official fix or patch is currently available, and no known exploits in the wild have been reported.
Potential Impact
Unauthorized users can create custom fields in Joomla! CMS via webservices endpoints due to improper access control. This could lead to unauthorized modifications of the CMS configuration or data structure, potentially impacting the integrity and security of the affected Joomla! installations.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is released, restrict access to webservices endpoints and monitor for suspicious activity related to custom field creation.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- Joomla
- Date Reserved
- 2026-05-26T16:47:13.550Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a4d4571c9d9e3dbe3a44f3b
Added to database: 07/07/2026, 18:29:05 UTC
Last enriched: 07/15/2026, 12:25:29 UTC
Last updated: 08/19/2026, 22:52:13 UTC
Views: 91
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