CVE-2026-56721

CamaleonCMS version 2.9.2 and earlier contains a privilege escalation vulnerability via insecure direct object reference (IDOR) that allows authenticated low-privileged attackers to overwrite any user's credentials by exploiting a parameter confusion flaw between the authorization filter and action body in the UsersController. Attackers can send a PATCH request to the updated_ajax endpoint setting params[:id] to their own user ID to pass the self-authorization check while simultaneously setting params[:user_id] to a victim's ID, causing the controller to load and mutate the victim's account, including overwriting administrator passwords to achieve full site takeover.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/owen2345/camaleon-cms
https://github.com/owen2345/camaleon-cms/commit/26345034523a505cb01615509b7f0a665e89ae3e
https://github.com/owen2345/camaleon-cms/pull/1185
https://www.vulncheck.com/advisories/camaleoncms-privilege-escalation-via-parameter-confusion-in-userscontroller

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-11 16:17

Updated : 2026-08-31 20:38

NVD link : CVE-2026-56721

Mitre link : CVE-2026-56721

CVE.ORG link : CVE-2026-56721

JSON object : View

Products Affected

No product.

CWE

CWE-639

Authorization Bypass Through User-Controlled Key

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