CVE-2026-50279
Craft CMS: Authorship spoofing in `entries/save-entry` via pre-check/post-mutation authorization gap
Impact
Craft CMS is a content management system (CMS). IN versions 5.0.0-RC1 and above prior to 5.9.21, theEntriesController::actionSaveEntry() performs entry-edit permission checks before request-controlled author changes are applied to the model, allowing for authorship spoofing. The subsequent author mutation path accepts attacker-supplied authors / author parameters and allows the change when the current user is one of the old authors. Because the controller does not re-run authorization after mutating the author list, a low-privileged user can reassign an entry’s authorship to another user without holding the dedicated peer-author-change permission. This issue has been fixed in version 5.9.21.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| composer | craftcms/cms | >= 5.0.0-RC1, < 5.9.21 | 5.9.21 |