CVE-2026-50283 Craft CMS: Unauthorized Deletion of Source Assets During File Replacement
Authenticated users can delete assets in unauthorized volumes by exploiting a permission check flaw during file replacement operations.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-50283?
CVE-2026-50283 is a medium-severity missing authorization vulnerability in craftcms cms, published on 1 Jul 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Craft CMS is a content management system (CMS). Versions 5.0.0-RC1 through 5.9.20, and 4.0.0-RC1 through 4.17.13 contain an authorization issue in the AssetsController::actionReplaceFile that can delete a source asset without source delete permission by supplying both assetId and sourceAssetId. AssetsController::actionReplaceFile() supports replacing a target asset file using another existing asset as the source. The action loads: assetId -> $assetToReplace and sourceAssetId -> $sourceAsset, then enforces replace permissions using ($assetToReplace ?: $sourceAsset). When both IDs are provided, this expression resolves to the target asset so no permission check is performed against the source asset volume. When both assets are present, Craft copies the source file into the target and then deletes the source asset. There is no deletion check for for the source asset. An authenticated user who can replace files in one volume can delete assets in another volume where they do not have delete permission, as long as they can obtain a sourceAssetId, leading to broken content references and data loss. This issue has been fixed in versions 4.17.14 and 5.9.21.
Which versions are affected by CVE-2026-50283?
4 open source packages ship an affected version, including craftcms/cms.
| Package | Affected | Fixed in |
|---|---|---|
craftcms/cms Packagist | From 4.0.0-RC1 | 4.17.14 |
craftcms/cms Packagist | From 4.0.0-RC1 | 4.17.14 |
craftcms/cms Packagist | From 5.0.0-RC1 | 5.9.21 |
craftcms/cms Packagist | From 5.0.0-RC1 | 5.9.21 |
How do I fix CVE-2026-50283?
Upgrade craftcms/cms to a fixed version for your release line: 4.17.14 or 5.9.21.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-50283 being exploited?
There is no known exploitation of CVE-2026-50283 in the wild and no public exploit code.
Sources
Also known as GHSA-qh45-9g5p-m2v4.