CVE-2026-92223 in Joomla
Summary
by MITRE • 09/29/2026
Joomla! Core - [20260910] - Core - Improper ACL checks for workflow stage changes in Joomla 5.0.0-5.4.8, 6.0.0-6.1.3 - An improper access check allows unauthorized users to update the workflow stage of inaccessible contents.
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Analysis
by VulDB Data Team • 09/29/2026
The vulnerability identified as CVE-20260910 represents a critical failure in the Access Control List (ACL) implementation within the Joomla! content management system, specifically affecting versions 5.0.0 through 5.4.8 and 6.0.0 through 6.1.3. This flaw resides in the core workflow engine responsible for managing state transitions of articles and other supported content types. In a properly secured environment, any operation that modifies the status or stage of a content item must verify not only whether the user has permission to edit the specific fields but also whether they have sufficient privileges to interact with the object as a whole. The identified defect bypasses this holistic check during workflow stage updates, allowing an attacker who possesses minimal editing permissions for certain sections to manipulate the lifecycle state of items that are otherwise inaccessible or restricted by higher-level ACL rules.
From a technical perspective, the root cause is classified under CWE-284 Improper Access Control and more specifically aligns with CWE-915 Improperly Controlled Modification of Dynamically-Determined Object Attributes. The vulnerability exploits the decoupling between field-level permission checks and object-level state transitions within the Joomla! framework. When a user submits a request to change the workflow stage, such as moving an article from draft to published or pending review, the backend logic fails to re-evaluate the global ACL permissions associated with that specific content item against the current user's profile. Instead, it relies on cached permission data or performs checks only on the fields being explicitly modified in the request payload. This architectural oversight means that a low-privileged user can effectively alter the visibility and status of high-security content by exploiting this gap in validation logic during the state change process.
The operational impact of this vulnerability is severe, as it enables unauthorized privilege escalation within the context of content management workflows. An attacker with basic editing rights could potentially publish sensitive articles that were intended to remain private or draft-only, thereby compromising data confidentiality and integrity. Furthermore, by manipulating workflow stages, an adversary can disrupt administrative processes, such as forcing items into a review queue without authorization or bypassing approval steps required for public-facing content. This undermines the trust model of the CMS, where administrators rely on strict role-based access controls to manage editorial workflows securely. The ability to alter states of inaccessible contents also facilitates potential denial-of-service conditions by cluttering workflow queues with unauthorized entries or causing inconsistencies in published site data that require manual intervention to resolve.
This vulnerability maps directly to several techniques within the MITRE ATT&CK framework, particularly T1078 Valid Accounts and T1548 Abuse Elevation Control Mechanism. The attacker leverages valid credentials but abuses elevation control mechanisms by exploiting flawed permission checks to perform actions beyond their assigned role. Additionally, it relates to T1229 Transference since the manipulation of workflow stages can be used to move malicious or misleading content through approval pipelines without proper oversight. For organizations running affected versions of Joomla!, immediate mitigation is required as this flaw allows for significant lateral movement within the application's permission structure.
To mitigate this risk, administrators must upgrade their Joomla! installations to a patched version that addresses these ACL checks immediately after release by the vendor. In the interim, if an update is not feasible due to compatibility constraints or other operational reasons, organizations should implement strict network-level access controls to restrict backend administrative interfaces from untrusted networks. Additionally, enabling comprehensive logging and monitoring for workflow stage changes can help detect anomalous activity indicative of exploitation attempts. Security teams should also review user roles and permissions regularly to ensure that the principle of least privilege is strictly enforced across all content categories, minimizing the potential blast radius if such a vulnerability were present in other components or future versions. Regular audits of ACL configurations are essential to maintain robust security postures within complex CMS environments where workflow logic intersects with access control systems.