Authorization bypass through user-controlled key in Craft CMS - #VU144278
Published: August 19, 2026
Vulnerability identifier: #VU144278
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-639
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to read, modify, or delete content across unauthorized sites.
The vulnerability exists due to authorization bypass through user-controlled key in the GraphQL entry mutation resolvers (`saveEntry`, `deleteEntry`) when processing a user-supplied `siteId` in mutation arguments. A remote user can supply a crafted `siteId` value to read, modify, or delete content across unauthorized sites.
The issue affects mutations because they read `siteId` directly instead of applying the site-scope filtering used by the query path, and deletion can remove the targeted element across all sites.
Affected software
Craft CMS
Remediation
Install security update from vendor's website.
Craft CMS - update to 5.10.11